Lithium is considered a dangerous metal by the Danish Environmental Protection Agency (Kjlholt et al., 2003) and is listed as such in the Australian Inventory of Chemical Substances (AICS, 2007). The US Environmental Protection Agency (EPA) recommends a threshold of 0.7 mg/L for Li in drinking water based on a Lowest Observable Adverse Effect Level resulting in nephrotoxicity in humans receiving long-term Li therapy for treatment of manic depressive disorders (Tripathi, 2011), but does not define a maximum contaminant level (US EPA, 2021). While Li is used in pharmaceuticals to treat depression, bipolar disorder, and mania (Loganathan et al., 2008; Mayo Clinic, n.d.; Swain, 2017), there is a suite of known side effects resulting from Li intake, including poor memory, unusual weakness, dizziness, slow heartbeat, renal failure, and interference with several biological processes (Mayo Clinic, n.d.; Tanveer et al., 2019; US EPA, 2008). Patients receiving lithium orally take between 300  1200 mg of Li two to three times a day (Mayo Clinic, n.d.). Therapeutic serum dosage is on the order of 10 mg/L Li in blood; at 20 mg/L, the concentration can be fatal to humans (Aral and Vecchio-Sadus, 2008). In plants, Li phytotoxicity manifests itself as necrosis, or breakdown of chlorophyll (Tanveer et al., 2019).


Archmagus George of the Sun

Table 1. Average bulk chemical composition and main minerals of the four studied hard-rock deposits (wt.%). Mineral abbreviations are as follows: Ab = albite; Kfs = K-feldspar; Qz = quartz; Znw = zinnwaldite; Tpz = topaz; Fl = fluorite; (Li)-Ms = (Li)-muscovite; Ap = apatite; Amb = amblygonite; Tur = tourmaline; Pl = plagioclase; Spd = spodumene.
	Cnovec		Homolka		Podles		Rappold Complex*
	Granite 	Greisen		Granite		Stock Granite	Dike Granite		Pegmatite
SiO2	73.93	69.25		72.93		73.80	70.10		74.05
TiO2	0.02	0.01		0.04		0.06	0.02		0.02
Al2O3	14.13	13.71		14.80		14.58	15.77		14.64
Fe2O3	0.30	2.76		0.84		0.30	0.11		1.89
FeO	0.64	1.81				0.88	0.67
MgO	0.10	0.02		0.16		0.04	0.02		0.10
MnO	0.08	0.38		0.05		0.02	0.04		0.47
CaO	0.60	0.44		0.50		0.39	0.43		0.51


Li2O	0.21	0.92		0.07		0.13	0.33		0.07
Na2O	3.79	0.08		3.93		3.19	4.10		5.04
K2O	3.04	3.28		4.14		4.46	4.25		1.75
P2O5	0.01	0.02		0.56		0.38	1.03		0.03
F	1.05	4.45		0.34		1.28	1.31
Major Minerals	Qz, Ab, Znw	Qz, Ab, Znw		Qz, Ab, Li-Ms, Or		Qz, Ab, Znw, Tpz	Qz, Kfs, Ab, Tpz, Znw		Kfs, Qz, Pl, Ms, Spd
Minor Li-/F-minerals	Tpz, Fl	Tpz, Fl		Tpz, Ap		Amb, Tur, Ap	Tur, Ap, Amb		Tur
Source	(Breiter et al., 2017)
(Breiter et al., 2017)
	(Breiter and Scharbert, 1995)
	(Breiter, 2002)
(Breiter, 2002)
	(Knoll et al., 2018)


*Sankt Radegund bei Graz pegmatites are part of the Rappold Complex, but no geochemical composition of those specific outcrops was available.
Aral and Vecchio-Sadus reviewed the available literature on the toxicity of Li and concluded that at natural background Li concentrations, its toxicity is relatively low for humans (Aral and Vecchio-Sadus, 2008). Additionally, researchers have also examined the possibility that elevated Li concentrations in drinking water may lead to a reduction of crime and suicide rates, but not all studies support this hypothesis (Kabacs et al., 2011; Ohgami et al., 2009; Oliveira et al., 2019). While there are no regulatory limits on the amount of Li in drinking water aside from the EPA-recommendation, the Australian Capital Territory set a limit on the amount of Li allowed to enter waterways (2.5 mg/L (EPR, 2005)). Based on the available information in the literature, we suggest that the Li distribution in the environment near Li deposits should be monitored.


Apart from Li, Li-micas also contain significant amounts of fluorine (F), which may be released to the environment during weathering. High concentrations of F- in water may cause fluorosis (Khairnar et al., 2015; Li et al., 2016; Perumal et al., 2013; Rango et al., 2012). The WHOs (WHO, 1999) threshold for F- concentration in drinking water is 1.5 mg/L. Ingesting water with F- concentrations between 1.5 and 3.0 mg/L leads to dental fluorosis, symptoms of which range from dental lesions and tooth discoloration to broken teeth (Yadav et al., 2009). Bones begin to show signs of fluorosis above 3.0 mg/L, with symptoms, such as, skeletal lesions, osteosclerosis, and changes in the structures of joints and limbs (Comba and Cinar, 2016). Severe skeletal fluorosis has been shown to interfere with the ability to breathe, as structural ribcage deformation affects proper lung function (Mandal et al.,


deformation affects proper lung function (Mandal et al., 2014). Fluoride can replace the hydroxyl group in hydroxyapatite, which makes up bones (Godebo et al., 2020; Kurdi, 2016; Srivastava and Lohani, 2015). The transformation of hydroxyapatite into fluorapatite has a negative impact on bone density, strength, collagen content and composition, and microstructure (Godebo et al., 2020). Globally, India is suffering the most from elevated F- concentrations in drinking water, but as elevated concentrations have also been observed elsewhere, F- levels are monitored in many parts of the world (Ali et al., 2016; Banerjee, 2015; Beltrn-Aguilar et al., 2010; Fordyce et al., 2007). Because both lepidolite and zinnwaldite, as well as amblygonite may contain considerable amounts of F, water sources near deposits that host these minerals should be analyzed for F- contents.


The goal of this research was to establish background levels of Li, F-, and other ionic species in waters around four hard-rock Li deposits in Central Europe, one of which is being actively explored and scheduled for production in the near future. If mining were to take place in one of these four deposits, this study provides pre-mining concentrations of these aqueous species and offers a benchmark for potentially required remediation. Additionally, this study aims to understand whether natural weathering of these deposits can lead to dangerous amounts of Li or F- in surface and drinking waters and to a potential public health concern. Finally, the geochemical data could also be used in exploration for Li deposits elsewhere.


### 2. Materials and Methods
#### 2.1. Geological Setting
We collected water samples near three Li-mica granite/greisen bodies and one spodumene pegmatite in Central Europe (Figure A1). The granites are products of the Variscan orogeny, which resulted from the collision between Gondwana and Laurasia (Kroner and Romer, 2013). The Variscan subduction ceased at around 340 Ma, but the subsequent isothermal exhumation of the subducted continental crust is thought to be responsible for Late Variscan high-temperature metamorphism and voluminous granitic magmatism (Kroner and Romer, 2013). On the other hand, the Rappold Complex, which includes the Sankt Radegund bei Graz spodumene pegmatites, resulted from of an Eo-Alpine intra-continental collision during the Cretaceous (Gaidies et al., 2008) and is a prominent unit in the Upper Austroapline basement nappes between the Wlz and Saualpe-Koralpe Complexes (Gaidies et al., 2008).
##### 2.1.1 Cnovec/Zinnwald, Czech Republic/Germany


Cnovec is located in the northwestern part of the Czech Republic (Figure A1), on the border with Germany, where the site is known as Zinnwald. The granite/greisen deposit stretches across the border (Figure 1). Geologically, these rocks belong to the Ore Mountains, also known by their German name Erzgebirge or Czech name Krun hory. Historically, Cnovec has been mined for tin and tungsten, but the mines are no longer in operation. Large quantities of Li, however, are hosted by the granites and greisen, representing the largest known Li deposit in Europe and the fourth largest non-brine deposit in the world (European Metals, 2019). Therefore, the site is currently being explored for Li mining. The deposit is rich in the Li-mica zinnwaldite, named after this locality. The host rock, a slightly peraluminous A-type granite, was extensively greisenized, i.e., altered due to interaction with volatiles during solidification of the magma (Breiter et


during solidification of the magma (Breiter et al., 2019, 2017). It is rich in Li2O (0.095  0.962 wt.%) and F (0.62  4.18 wt.%), but poor in P2O5 ( 0.023 wt.%, Table 1, (Breiter et al., 2017)), and contains elevated amounts of Nb, Sn, Ta, and W. The major minerals present are quartz, albite, and zinnwaldite; minor minerals include topaz, fluorite, cassiterite, and zircon (Breiter, 2012). Zinnwaldite, occurring down to a depth of 735 m below the surface, is rich in Fe (8.9  15.2 wt.% FeO), Li2O (2.0  4.4 wt.%), and F (7.0  8.6 wt.%; (Breiter et al., 2019)). The granites were emplaced into the Teplice Rhyolite (Breiter et al., 2019) (see Fig. 1).


This site is especially interesting for its history of underground Sn and W mining, which has created tunnels that are now abandoned and drain percolating water. In addition, sand representing old tailings, has been deposited near the topographical peak of the area, where it is exposed to rain and vegetation. This sand is composed of zinnwaldite, quartz, and albite, and contains 0.27 wt.% Li2O (Czech Geological Survey, 2018).
##### 2.1.2. Homolka, Czech Republic


The Homolka granite, occurring in the southern Czech Republic (Figures A1, A2), close to the border with Austria, is in the NW part of the Moldanubian pluton of the South-Bohemian batholith (Breiter and Scharbert, 1995). It is a peraluminous granite rich in Li2O (0.16 wt.%), Rb (400  1500 mg/kg), F (0.5  1.0 wt.%), P2O5 (0.5  1.0 wt.%), Sn, Nb, and Ta, and poor in Ti, Mg, Fe, Ca, Sr, Ba, Zr, and REE (Table 1, (Breiter and Scharbert, 1995)). The major minerals are quartz, albite, orthoclase, and a Li-muscovite, whereas the accessory minerals are topaz, apatite, cassiterite, ferrocolumbite, and rutile (Breiter and Scharbert, 1995). The Li-muscovite is rich in Li2O (1.5  2.15 wt.%) and F (1.7  2.6 wt.%, (Breiter and Scharbert, 1995)).


wt.%, (Breiter and Scharbert, 1995)). The Homolka granite has not been mined and is not currently being considered an economic resource of Li, but it forms a large (6 km2), well defined outcrop, surrounded by two-mica granites: Lsenice to the West (Two-Mica Granite in Fig. A2) with no available information on F, Li2O, or P2O5 contents (Ren et al., 2003), and Eisgarn to the East and South (Porphyritic Two-Mica Granite in Fig. A2), which contains an average of 0.22 wt.% F, 0.03 wt.% Li2O, and 0.37 wt.% of P2O5 (Breiter and Scharbert, 1998).


##### 2.1.3. Podles, Czech Republic


The Podles granite, located in the western Czech Republic (Figures A1, A3) in the Ore Mountains, comprises two types of Li-enriched rocks, the Podles stock granite and a dike granite (Breiter, 2002). Both rock types are relatively rich in incompatible elements, such as Li2O (0.033  0.445 wt.%), Rb (< 2754 mg/kg), Cs (< 253 mg/kg), Sn (< 65 mg/kg), and W (< 99 mg/kg), as well as F (0.6  2.4 wt%) and P2O5 (0.4  1.5 wt%), whereby the stock is generally more enriched (Breiter, 2002). One of these dikes (the thickest found, 7 m across) outcrops in an abandoned quarry, from which granite was extracted (Breiter, 2004) and which floods during major rain events. The Li is hosted by zinnwaldite that is polylithionite-rich in the stock granite, but siderophyllite-rich in the dike granite (Breiter, 2002). The other major minerals are


(Breiter, 2002). The other major minerals are quartz, albite and topaz in the stock granite, and quartz, K-feldspar, albite, and topaz in the dike Additionally, amblygonite and tourmaline are also reported as Li-bearing minerals (Breiter, 2002). Whereas the Podles granite stock and dike granites make up a relatively small area, the surrounding albite-biotite granites have above-average Li2O (~0.033 wt.% (Breiter et al., 2005)) and F (0.5  1.0 wt.% (Breiter et al., 2006)) contents as well. There is also significant tin mineralization (cassiterite) in many parts of the area. The country rock of the granites consists of phyllite.


##### 2.1.4. Sankt Radegund bei Graz, Austria
There are over 20 known spodumene pegmatites in the Eastern Alps of Austria, which formed during the Cretaceous (Gaidies et al., 2008) and are spatially associated with leucogranites and barren pegmatites (Knoll et al., 2018). In addition to spodumene, the pegmatites contain K-feldspar, quartz, plagioclase, and muscovite, as well as minor garnet and tourmaline (Knoll et al., 2018). The spodumene pegmatites occur as dikes that were intruded into metamorphic rocks. We sampled stream water close to several known pegmatite outcrops near the town of Sankt Radegund bei Graz, Styria (Figures A1, A4). Their lengths are at least 15  20 m each, known to be at least 1.5  3 m thick, and geologically are part of the Rappold Complex (Schuster et al., 2019). The bulk-rock chemical composition given in Table 1 is from a different pegmatite within the Rappold Complex, because the outcrops near which we sampled did not have geochemical data available. The host rocks of the spodumene pegmatite outcrops in the sampling area are paragneiss and mica-schist; other prominent metamorphic rocks occurring within the studied watershed include marble and occasional dolomite, which both belong to the Schckelkalk Formation (Flgel et al., 2011; Knoll et al., 2018).
#### 2.2. Sampling


#### 2.2. Sampling
Hydrology (Figures 1 and A2-A4) was mapped in ArcGIS (Version 10.5) using the Hydrology toolset with the 30-Meter Shuttle Radar Topography Mission digital elevation model (DEM) downloaded from https://dwtkns.com/srtm30m/. Water-sampling points were then selected to best reflect the environment near a given deposit by aiming for sample collection at stream intersections, where available, to represent the largest possible area. Samples were collected within a given deposit, downstream from the deposit, as well as upstream where possible. The latter was not achievable in the cases of Cnovec and Homolka, where the deposits represent the highest-elevation peaks in the area (see Fig. 1, 2). The general sampling density ranged from 1 sample per 0.5 km2 to 1 sample per 3 km2, depending on the nature and area of the deposit and the number and size of nearby streams. Where possible, we sampled streams that were similar in terms of water flow, slope, and shape to minimize erosion effects on the geochemical signatures but, as expected, streams closer to the deposits and at higher elevations tended to be smaller than those downstream. Additionally, some streams could only be accessed at a few places as they were running through private properties, therefore limiting our efforts in this realm. Sampling took place in July and August 2020.


Our sampling procedure followed (Hem, 1985), except for the filtration step. We chose not to filter our samples in order to not only quantify the dissolved load, but also the exchangeable fraction to obtain a better understanding of the mobility of Li in these environments, as suggested by the US EPA (Puls and Barcelona, 1989). Water samples were collected into 250 mL polyethylene bottles. Temperature, pH, dissolved oxygen, and electric conductivity were determined directly in the field using a handheld Vernier digital probe (LabQuest 2). Alkalinity was measured in the field using an Hach 2444301 Alkalinity Test Kit, Model AL-AP. The samples were subsequently acidified to pH 2 with nitric acid and stored in a refrigerator at ~4C until further analysis; the only exception was the air travel from the Czech Republic to Philadelphia, USA, during which the samples were in the cargo hold of the airplane, where the temperature typically is ~7C.


Average precipitation over the area of the Czech Republic for July of 2020 was 68 mm, lower than the 88 mm average for July between 1981 and 2010 (Czech Hydrometeorological Service, 2020a). August was wetter than normal, with 111 mm compared with the 80 mm average (Czech Hydrometeorological Service, 2020a). Mean daily temperatures were normal for July and hotter for August, at 17.7C and 18.8C, respectively, compared to long-term average values between 1981 and 2020 of 17.8C and 17.3C, respectively (Czech Hydrometeorological Service, 2020b). In general, the Czech Republic, especially the western and northwestern (Podles and Cnovec sites) regions, was experiencing a drought in the summer of 2020, apparent in the field as many desired sampling-point streams were dried out (Gvozdikova et al., 2020; Svabenicka et al., 2020). Our labeling scheme follows the first letter of the deposit (e.g., C for Cnovec) and numbers from 1 up, skipping numbers where we aimed to sample, but the site was dry.


The water from the Cnovec Deposit was sampled on August 11, 2020. This site is on the eastern flank of the Erzgebirge. The flow of the nearest monitored river, the Blina, was much lower in July 2020 than in previous years (Czech Hydrometeorological Service, 2020c). This was evident in the field, as four sites we aimed to sample were dried up. The weather alternated between cloudy and sunny, and the temperature ranged from 18 to 24C. A total of 10 samples were collected, one of which was an underground sample (labeled CMine), collected on the German side of the deposit in an old tin mine, which now serves as a tourist attraction.

The streams around the Homolka Granite deposit were sampled on July 13 and July 14, 2020. The flow rate of the Lsenice river (connecting H10 and H11 in Figure A2) shows slightly above-average values relative to historical data (Czech Hydrometeorological Service, 2020c). During sampling, the weather was sunny, ranging from 14  20C over the course of the day. A total of 16 samples were collected.

The Podles Granite water was collected on July 29, 2020. The site is on the eastern flank of the Erzgebirge, in the rain shadow; in 2020, it received even less rainfall than normal (Svabenicka et al., 2020). Recorded flow for July 2020 in the nearest monitored river, the Ohe, was significantly below the historic mean or median values (Czech Hydrometeorological Service, 2020c). Several sampling sites were dry here as well. The weather was warm (20  25C) and sunny during the sampling. A total of 11 samples were collected.


The water samples from the Sankt Radegund Pegmatite field were collected on August 8, 2020. The water level of the nearest monitored river, the Raab river, was slightly above average values during the sampling (Austrian Hydrometeorological Service, 2020). The day was sunny, with temperatures ranging from 19 to 24 C. A total of 10 samples were collected.
#### 2.3. Geochemical Analysis
The water samples were transported to the Department of Earth and Environmental Science (EES) at the University of Pennsylvania in order to perform chemical analyses by Inductively-Coupled Plasma Optical Emission Spectrometry (ICP-OES) and Ion Chromatography (IC). The following elements were analyzed by ICP-OES: Li, Na, K, Rb, Cs, Mg, Ca, Mn, Fe, Al, Si, and Cu. Using IC, the following anion concentrations were determined: SO42-, Cl-, F-, and PO43-. The HCO3- content was calculated from the alkalinity. The excess nitrate concentration, which resulted from the acidification of our samples, led to an overlap with the sulfate peak on the ion chromatograms. Therefore, sulfur was subsequently also analyzed by ICP-OES. We used six preliminary non-acidified samples from the Cnovec area, collected in the summer of 2019, that we analyzed on both IC and ICP-OES and the sulfate concentrations agreed well (within 92%).
#### 2.4. Statistical Analysis
One-way cross correlation of all of our analyzed elements and anions as well as physical parameters (elevation, dissolved oxygen, pH, temperature, alkalinity, conductivity) was performed in Python (version 3), using the numpy as well as scipy.stats packages. Linear regressions of several of the more correlated variable pairs were also calculated.


#### 2.5. Geochemical Modeling
Speciation and mineral saturation indices were modeled using PHREEQC (version 3.5, run on a Mac version 10.14, (Parkhust and Appelo, 2013)). Saturation indices allow us to make thermodynamic predictions about certain mineral precipitation/dissolution processes. For these calculations, we used the Lawrence Livermore National Laboratory thermodynamic database (llnl.dat), distributed together with PHREEQC, and augmented it by the thermodynamic data (log K = 15.6847) for zinnwaldite from (Ogorodova et al., 2010). We used the following dissolution equation of zinnwaldite:
KLiFeAl2Si3O10F2 + 8 H+ = K+ + Li+ + 2 Al3+ + Fe2+ + 2 F- + 3 SiO2 + 4 H2O			(1)
modeled with the theoretical composition as presented in (Ogorodova et al., 2010) and shown in equation (1).


Additionally, inverse modeling with PHREEQC was carried out to complement the saturation indices and examine, using a different approach, which minerals in the Cnovec area have most likely been dissolved. The method was described in (Zhu and Anderson, 2002). We assume the initial water is rainwater with a composition of that sampled at the Bedichov, CZE monitoring site (Czech Hydrometeorological Service, 2007). The final water is that of the collected stream samples. The increase of the chemical constituents in the final water, compared to the rainwater, was assumed to be caused by the weathering of local rocks. Specifically, we assume that the Li is derived from the dissolution of zinnwaldite, F- from the dissolution of zinnwaldite and fluorite, Cl- from biotite (in the Teplice Rhyolite) and atmospherically dry-deposited halite (Drever, 1988), Mg from biotite, and sulfate from gypsum. The mass balance of Al and Si was achieved from the dissolution


of Al and Si was achieved from the dissolution of feldspars (albite, K-feldspar and anorthite), biotite (Mg-endmember phlogopite), and zinnwaldite, and from precipitation of the three clay minerals kaolinite (Al2(Si2O5)(OH)4), allophane (Al2O3)(SiO2)1.3-22.5-3H2O, amorphous), and imogolite (Al2SiO3(OH)4). Apatite (with a theoretical composition of Ca5(PO4)3(F0.8,(OH)0.2) was also included as a potential source of Ca and F-. Goethite was included as a sink of Fe. Ion exchange between clays and Li, Na, K, and Ca was allowed, and is presented as LiX, NaX, KX, and CaX2 (Carroll, 1959); Li is scrubbed by clays very rapidly (Li and Liu, 2020; von Strandmann et al., 2020), making clay adsorption of Li essential to realistic modeling efforts. As the streams are open to the atmosphere, CO2 (g) and O2


to the atmosphere, CO2 (g) and O2 (g) were used as phases as well. As there can be many combinations of mineral-dissolution processes resulting in the same chemical composition of water, the standard approach is to only consider minimal models (Parkhust and Appelo, 2013), i.e., the fewest number of phases involved in the model, leading to the most essential geochemical reactions considered.


### 3. Results
#### 3.1. Geochemical Analysis
The entire set of geochemical data for all water samples can be found in the Appendix, Table A1. Generally, the samples containing the highest amounts of total dissolved solids (TDS) are from the Cnovec site, with sample C14 having the highest values. The highest Li concentrations are observed in the waters from the Cnovec and Homolka sites (Figure 2). Fluoride is highly concentrated in the Cnovec sites, which are also most enriched in Na and Cl. The Homolka site is richer in Al and SO42- than the other sites. Generally, iron and phosphate ions are more concentrated in the Podles site. Sankt Radegund bei Graz has the highest arithmetic mean concentrations of Mg, Ca, SiO2, and HCO3-. Copper showed almost no variation across the four samples and was mostly near the ICP-OES detection limit.


The major cation and anion distributions of all samples are shown in a Piper diagram (Figure 3). The dominant cations are Ca2+ and Na+, whereas the three major anions are more evenly represented. Waters draining the pegmatite at Sankt Radegund bei Graz are distinct from the other sites, being Ca-HCO3 waters (Figure 3). Streams around the three Li-mica deposits range from calcic to sodic waters, with a few in the Podles site being Mg-rich. Although individual stream samples from these three deposits span the range between sulfate and chloride waters, those from the Homolka site are mostly sulfate-dominated, those from the Cnovec site include the most chloride-enriched, leaving the waters from Podles plotting in between. Upstream samples/samples closer to the source rocks are generally more concentrated in Li and F relative to downstream samples. The mine-drainage water (CMine) is a Ca-Cl water type, and so is sample C14, which is richest in Li and F-.
An important result to note is that the stoichiometric ion imbalance (IB) of some of the samples is considerably non-zero (arithmetic mean is 12.9%, with a standard deviation of 6.5%), the highest being 57% for sample C12 (see below). This imbalance drops by about a half for most samples when the speciated imbalance is calculated (using PHREEQC) rather than the stoichiometric imbalance; for C12, for example, the speciated IB has a value of 33.3%.
### 3.2. Statistical Analysis


The arithmetic mean, standard deviation, and maximum concentrations of Li and F- in the waters from the four studied areas are listed in Table 2. Of note are the relatively large standard deviations of Li concentrations for the Cnovec and Homolka sites as well as the large standard deviation for the Cnovec F- concentrations. The Cnovec and Homolka sites show nearly identical maximum and arithmetic mean Li concentrations, yet very different F- concentrations. Correlations between variable element pairs of interest are shown in Table 3, with the cross-correlations of all parameters displayed in the Appendix (Tables A2-A5). The pairs presented in Table 3 were chosen based on chemical makeup of the Li-minerals and magnesium based on its similar ionic radius, resulting in similar environmental behavior (Ogawa et al., 2014). Several strong and significant correlations are observed: between Li and F- in Cnovec and Homolka, Li and Al in the same deposits, Li and Mg in Cnovec


same deposits, Li and Mg in Cnovec and Podles, albeit of opposite signs, Li and Si in Homolka, Li and K in Cnovec and Sankt Radegund bei Graz, and F- and PO43- in Podles. Amongst ions not presented in Table 3 (Tables A2-A5), strong and significant correlations (r > 0.8, p < 0.05) observed in Cnovec are: Li and Ca, Li and K, Li and Cl, Na and Ca, Na and K, Na and Cl, Mg and Ca, Mg and Al, Mg and Cl, Mg and SO42-, Mg and HCO3-, K and Cl-, Al and Cl-, Al and SO42-, Fe and Mn, Cl- and HCO3-, and SO42- and HCO3-. In Homolka, there are significantly fewer strong and significant correlations: Na and Mg, Na and Ca, and Mg and Ca. In Podles, strong and significant correlations are observed between Na and Ca, Na and K, Na and Cl-, Ca and


Ca, Na and K, Na and Cl-, Ca and K, Ca and Cl-, K and Cl-, and Fe and Mn. Finally, Sankt Radegund bei Graz presents only Ca and HCO3- as a strong and significant correlation.


Table 2. Descriptive statistics of Li and F ions in the waters at our four studied sites (mg/L).
	Lithium		Fluoride
Deposit	Mean	Std Dev	Max		Mean	Std Dev	Max		n
Cnovec	0.011	0.012	0.036		1.365	1.408	3.806		10
Homolka	0.013	0.009	0.035		0.321	0.112	0.544		16
Podles	0.006	0.001	0.009		0.103	0.022	0.140		11
Sankt Radegund	0.005	0.002	0.007		0.062	0.016	0.088		10


Table 3. Correlation coefficients (r) between Li concentration and that of several ions of interest and between F- and phosphate ions. Star (*) highlights significant correlations (p < 0.05).
Deposit	F vs. Li	Si vs. Li	Fe vs. Li	Al vs. Li	Mg vs. Li	K vs. Li	F vs. PO4
Cnovec	0.679*	0.485	0.146	0.764*	0.776*	0.802*	-0.110
Homolka	0.701*	0.853*	0.162	0.792*	0.458	0.231	-0.452
Podles	0.532	0.319	0.043	0.448	-0.799*	-0.049	0.604*
Sankt R.	-0.270	0.567	0.066	0.140	0.507	0.738*	0.519


Special interest was placed on the strong correlation, especially at Cnovec and Homolka, between Li and F- (Fig. 4). In the Cnovec dataset, sample C12, with its low Li (0.003 mg/L) but high F- (3.566 mg/L) contents, is an outlier, which affects the slope of the regression line, causing it to not go through the population of samples with lower Li concentrations (solid green line in Fig. 4). Therefore, we calculated a second correlation for the Cnovec samples without sample C12, yielding a much better correlation (r = 0.985; dotted green line in Fig. 4). The molar F:Li values in zinnwaldite are about 1.5, depending on the exact composition (a microprobe analysis of a Zinnwald mica shows a Li2O content of 3.9 wt.%, and a F content of 6.5 wt.%, yielding a molar F:Li ratio of 1.31 (Tischendorf, 1997)), yet the slope of correlation lines between the corresponding aqueous ionic species is around 30 (36 without the C12 sample) for the two correlation lines (Fig. 4). The Homolka and Podles sites have comparable slopes of ~3, but the correlation is not significant (p = 0.061) in the Podles site. On the other hand, the correlation for the Homolka samples is better (r = 0.701) and highly significant (p = 0.005). The Sankt Radegund bei Graz site shows no correlation (r = -0.270, p = 0.451).


The Al vs. Li relationship adds additional insight, as it is strong and significant in both the Cnovec and the Homolka datasets (Table 3). Similar to the comparison of the F:Li values between the water samples and micas, we would expect the molar Al:Li values to be between 1 and 2, if the two elements were derived exclusively from the micas, but the slopes of the best-fit lines are about 16 and 14 for Cnovec and Homolka, respectively. The relationship between Si and Al is strong and significant in the Homolka site (r = 0.785, p = 0.001, Table A3) and the slope of the best fit line is 4.5, close to pure feldspar dissolution which would plot near 3. The strong (r = 0.853) and significant (p = 0.000) relationship between Si and Li in the Homolka site leads to a best-fit line slope for the correlation line between the two elements of about 98, much higher than an expected value of 2-4 should both elements be released


expected value of 2-4 should both elements be released from micas only. The strong and significant Mg vs. Li correlations in Cnovec (r = 0.776, p = 0.008) and Podles (r = -0.799, p = 0.002) are interesting as some Mg could likely be substituted into zinnwaldite and some Li into biotite. The strong and significant correlation of K vs. Li in the Cnovec site leads to a best-fit line slope of 15, significantly above the 1:1 ratio expected should they be leached from the same Li-micas, but nearly the same value as for Al vs. Li. The strong and significant correlation between F- and PO43- at the Podles site seems to reflect the presence in the rocks of amblygonite and apatite.


3.3. Geochemical Modeling


In general, the water samples examined in greater detail with geochemical modeling tools are undersaturated with respect to zinnwaldite, fluorite, and the feldspars (Figure 5) and supersaturated with respect to kaolinite, allophane, and imogolite (not shown in Figure 5 for easier visualization of the other minerals of interest). In our inverse modeling inputs, this result allowed us to force the undersaturated minerals to dissolve only and the supersaturated phases to precipitate only.

To examine the outlier in the Cnovec deposit (sample C12) in greater detail, saturation indices (SIs) of minerals known to be present in the area were modeled. Special interest was placed on fluorite because of the high F-, but low Li contents determined for the water at the C12 site (see Fig. 4). Zinnwaldite, albite and K-feldspar are undersaturated at site C12, whereas quartz is near saturation (Fig. 5); fluorite and fluorapatite are also undersaturated. Calcite is included in the model to compare to fluorite at the C12 site. The C14 site features the largest SIs for all minerals (except fluorapatite, at C5), whereby the water appears to be oversaturated with respect to K-feldspar, albite, quartz and fluorapatite. The SIs for the mine water (CMine) are elevated as well, but not significantly higher than, for example, the waters at C3 or C5 (with the exception of albite), neither of which are rich in F- or Li. In general, the waters are undersaturated with respect to the modeled minerals, except for occasionally K-feldspar, albite, and fluorapatite, and they are near equilibrium for quartz and fluorite at all sites.


The results of the inverse modeling for the water sample from the mine shaft (CMine) and for the fluoride-enriched samples C12 and C14 are provided in Table 4. The composition of the initial rainwater is given in Table A6. We were able to produce several minimal inverse models in each case. We used an uncertainty of 0.05 for CMine, but had to increase it to 0.10 for C12 and 0.15 for C14 to produce balanced models. An uncertainty of 1 means that any initial water is allowed to evolve into any final water; as the number increases, it means that there are likely processes at play that were not accounted for in the modeling (e.g., absorption by vegetation, kinetics). In C14, two models are produced with the only major difference being kaolinite precipitation as opposed to allophane precipitation, which then changes the other phases accordingly. In both models, six-times more fluorite is dissolved compared to zinnwaldite. None of the feldspars nor apatite are predicted


None of the feldspars nor apatite are predicted to supply ions into the solution. The modeling results further suggest that monovalent cations (Li, Na, and K) are predicted to be scrubbed from the solution by clays in favor of Ca, which would be released from the clays into the solution. In C12, five models are produced, with models 1,2,3, and 5 distinguished mostly by the types of clays that precipitate and feldspars that dissolve. Model 4 is different from the other models as significantly more zinnwaldite (99x) is predicted to dissolve. In Models 1,2,3, and 5, fluorite supplies nearly ~232x more F-; in Model 4, this ratio drops to 1.35. Ion exchange suggests Li and K being bound to clays, thus releasing Na and Ca. At the CMine site, nine minimal inverse models were produced. There are mostly two groups of models: Models 1,7, and 8, and Models 2,3,4,5,6, and 9. According to the first group


and 9. According to the first group of models, the same amounts of zinnwaldite and fluorite are dissolved. The other group predicts no fluorite dissolution, suggesting that all F- is derived from zinnwaldite. The major differences within the two groups of models are the Si-Al balance of which feldspars dissolve and which clays precipitate. The ion exchange is similar to C14 in that monovalent cations are scrubbed from solution and Ca released into the solution. At all sites and in all models, CO2 and O2 are removed from the atmosphere and brought into the solution.


Table 4. Precipitation (-)/dissolution (+) of phases (in mmol) predicted to explain the observed water composition via inverse modeling. Phases are presented in bold. Rainwater from the Bedichov (Table A6, Czech Hydrometeorological Service, 2007) station was used as initial water. Uncertainty used in the models is 15% for C14, 10% for C12, and 5% for CMine.
C14	Zinnwaldite	Fluorite	Albite	Anorthite	K-Feldspar	Apatite	Biotite	Gypsum	Kaolinite	Goethite	Halite	Allophane	Imogolite	LiX	NaX	KX	CaX2	CO2(g)	O2(g)
Model 1	0.0140	0.0855	0.0000	0.0000	0.0000	0.0000	0.1524	0.4770	-0.0360	0.0000	2.7544	0.0000	0.0000	-0.0088	-1.1377	-0.0750	0.6108	1.1323	0.0029
Model 2	0.0140	0.0855	0.0000	0.0000	0.0000	0.0000	0.1457	0.4770	0.0000	0.0000	2.7611	-0.0327	0.0000	-0.0088	-1.1444	-0.0683	0.6108	1.1323	0.0029


C12	Zinnwaldite	Fluorite	Albite	Anorthite	K-Feldspar	Apatite	Biotite	Gypsum	Kaolinite	Goethite	Halite	Allophane	Imogolite	LiX	NaX	KX	CaX2	CO2(g)	O2(g)
Model 1	0.0004	0.0927	0.0000	0.1259	0.0000	0.0000	0.0030	0.2648	-0.0861	-0.0004	0.0000	0.0000	-0.0392	0.0000	0.8234	-0.4557	0.0880	0.6189	0.0001
Model 2	0.0004	0.0927	0.0000	0.1161	0.0196	0.0000	0.0030	0.2648	-0.1253	-0.0004	0.0000	0.0000	0.0000	0.0000	0.8234	-0.4459	0.0684	0.6189	0.0001
Model 3	0.0004	0.0927	0.0196	0.1161	0.0000	0.0000	0.0030	0.2648	-0.1253	-0.0004	0.0000	0.0000	0.0000	0.0000	0.8039	-0.4459	0.0880	0.6189	0.0001


Model 4	0.0396	0.0536	0.0000	0.1259	0.0000	0.0000	0.0030	0.2648	-0.1644	-0.0396	0.0000	0.0000	0.0000	-0.0392	0.8234	-0.4166	0.0489	0.6189	0.0099
Model 5	0.0004	0.0927	0.0000	0.1259	0.0000	0.0000	0.0030	0.2648	-0.0298	-0.0004	0.0000	-0.0955	0.0000	0.0000	0.8234	-0.4557	0.0880	0.6189	0.0001
CMine	Zinnwaldite	Fluorite	Albite	Anorthite	K-Feldspar	Apatite	Biotite	Gypsum	Kaolinite	Goethite	Halite	Allophane	Imogolite	LiX	NaX	KX	CaX2	CO2(g)	O2(g)
Model 1	0.0345	0.0345	0.0495	0.0000	0.0348	0.0000	0.0245	0.1443	0.0000	-0.0337	1.6906	0.0000	-0.0823	-0.0302	-0.7614	0.0000	0.3958	0.5425	0.3055


Model 2	0.0691	0.0000	0.0000	0.0000	0.0842	0.0000	0.0245	0.1443	0.0000	-0.0683	1.6906	-0.1169	0.0000	-0.0648	-0.7119	-0.0840	0.4303	0.5425	0.3141
Model 3	0.0690	0.0000	0.0498	0.0171	0.0000	0.0000	0.0245	0.1443	0.0000	-0.0682	1.6906	0.0000	-0.1168	-0.0647	-0.7617	0.0000	0.4132	0.5425	0.3141
Model 4	0.0690	0.0000	0.0842	0.0000	0.0000	0.0000	0.0245	0.1442	0.0000	-0.0682	1.6906	-0.1169	0.0000	-0.0647	-0.7961	0.0000	0.4304	0.5425	0.3141


Model 5	0.0725	0.0000	0.0000	0.0000	0.0994	0.0000	0.0232	0.1374	-0.1276	-0.0717	1.6898	0.0000	0.0000	-0.0682	-0.7048	-0.1014	0.4372	0.5425	0.3150
Model 6	0.0706	0.0000	0.1004	0.0000	0.0000	0.0000	0.0232	0.1374	-0.1261	-0.0697	1.6889	0.0000	0.0000	-0.0662	-0.8082	0.0000	0.4372	0.5425	0.3145
Model 7	0.0345	0.0345	0.0000	0.0000	0.0843	0.0000	0.0245	0.1443	0.0000	-0.0337	1.6906	0.0000	-0.0823	-0.0302	-0.7119	-0.0495	0.3958	0.5425	0.3055


Model 8	0.0345	0.0345	0.0843	0.0000	0.0000	0.0000	0.0245	0.1443	0.0000	-0.0337	1.6906	0.0000	-0.0823	-0.0302	-0.7962	0.0348	0.3958	0.5425	0.3055
Model 9	0.0690	0.0000	0.0000	0.0173	0.0498	0.0000	0.0245	0.1443	0.0000	-0.0682	1.6906	0.0000	-0.1169	-0.0647	-0.7119	-0.0495	0.4131	0.5425	0.3141

### 4. Discussion
The Li concentrations measured in this study are elevated (over 0.02 mg/L) in five samples, and on average (for Cnovec and Homolka), they tend to plot above average values reported in other studies that measured Li in surface waters (Figure 6). For Podles and Sankt Radegund bei Graz, the Li values resemble typical background values reported in the literature (~0.01 mg/L, (Aral and Vecchio-Sadus, 2008; Kavanagh et al., 2017; Rodrigues et al., 2019)).


The Cnovec and Homolka mean and median Li concentrations are above those of known drinking water concentrations in Japan and England (Kabacs et al., 2011; Ohgami et al., 2009), the average (which average not specified in the publication) of background Czech waters (n = 5,765), and above the Mackenzie river (Millot et al., 2010), but lower relative to the waters around spodumene deposits in SE Ireland and Portugal ((Kavanagh et al., 2017; Rodrigues et al., 2019), Figure 6). It is important to note that in the SE Ireland study, the Li concentrations measured in the month of July were the lowest (median < 0.01 mg/L) amongst March, May, July, and September, with no correlation to the total amount of precipitation during those months (Kavanagh et al., 2017). However, we believe it is also important to point out that during the collection of our water samples, it was a relatively dry period (see above), which may have affected the Li


period (see above), which may have affected the Li concentrations not only by lowering the weathering intensity but also the dilution effects, therefore the net impact of precipitation is difficult to predict. The maximum concentrations we observed are not nearly as elevated as the outliers in most other studies shown in Figure 6, including the nationwide geochemical study of Czech surface waters, which reported the highest Li concentration (0.114 mg/L) from an area of Permian-Carbonian, Mesozoic, and Tertiary sediments, without any additional details (Chuman et al., 2013). The highest surface water Li concentrations are known from northern Chile near Li-brine deposits, where the concentrations can reach 20 mg/L (Figueroa et al., 2012), about three orders of magnitude larger than the arithmetic mean concentrations reported in our study and in the studies of waters near spodumene deposits in SE Ireland and Portugal (see above). Aral and Vecchio-Sadus reported on communities in Chile using water


reported on communities in Chile using water with Li concentrations approaching 10 mg/L, with no reported adverse health effects, although acquired tolerance may be a factor (Aral and Vecchio-Sadus, 2008). The concentrations we determined are much lower and, moreover, considerably below the EPA-recommended 0.7 mg/L threshold. We therefore conclude that there is likely no public health risk resulting from the Li concentrations of the waters examined for this paper, but additional sampling during spring/fall should be performed for a more complete assessment.


The stream water F- concentrations were very high around the Cnovec deposit, with a maximum value of 3.8 mg/L (Table 2), well above the WHO drinking water limit of 1.5 mg/L (WHO, 1999). At these concentrations, long-term exposure to this water could result in skeletal fluorosis (Mandal et al., 2014). The arithmetic mean F- concentrations at Cnovec, however, are slightly below the WHO drinking water limit of 1.5 mg/L (see Fig. 7). The arithmetic mean F- concentrations at Cnovec, on the other hand, are much higher than the average concentrations from the Czech Republic (Fig. 7). Whereas the Homolka waters are not nearly as enriched in F- as those at the Cnovec site  likely due to the smaller proportion of F in the respective host rocks (Table 1, (Breiter, 2012; Breiter and Scharbert, 1995))  they are still considerably richer in F- than the typical concentrations in Czech waters (Fig. 7). The mean and median F- concentrations at the Podles site are comparable to the overall concentrations of the Czech Republic, and the waters at the Sankt Radegund bei Graz site did not contain elevated amounts of F- (Table 2, Fig. 7).


The arithmetic mean of the absolute stoichiometric ion imbalance over all of our samples (IB = 12.86%) is above the generally accepted 5%, but this result is not uncommon in the literature (Fritz, 1994). It can likely be explained by the addition of nitric acid, which resulted in the following four possible errors: 1) it made us unable to measure nitrate and nitrite concentrations and therefore, our anion concentration sum is lower than the true anion concentration sum; in fact, the anion sum is lower than the cation sum in most samples (37 out of 47 samples); 2) we measured sulphate by ICP-OES due to the nitrate peak being too dominant over the sulphate one seen by IC; when analyzing a non-acidified set of preliminary samples from the same area collected in the summer of 2019 (Table A7, arithmetic mean IB = 4.08%) using both the ICP-OES and the IC, the ICP-OES data for sulphate agreed with the IC data at 92%,


sulphate agreed with the IC data at 92%, therefore reporting slightly lower sulphate concentrations than on the IC; cation concentrations were very comparable between the two datasets (compare Tables A1 and A7); 3) alkalinity, used to calculate bicarbonate and carbonate concentrations, was measured with a titration kit in the field, potentially leading to these values also being slightly incompatible with what we would see on the IC; large IB values are in fact commonly blamed on the field alkalinity measurement (Fritz, 1994); and 4) there is a possibility that an important cation for some samples has not been measured, which could explain the 10 samples (e.g., C12, H2) where the cation sum was lower than the anion sum. Additionally, the choice to not filter our samples could also have led to larger IBs due to the possible presence of colloids in our water samples, which may dissolve during acidification (Deutsch and Siegel, 1997). Finally, the speciated IB is typically about half that


Finally, the speciated IB is typically about half that of the stoichiometric IB and, in fact, it is <5% for the majority of our samples, and in our most imbalanced sample (C12) it has a value of 33.3%.


The highest concentrations of both Li and F- are found in sample C14. An old mining shaft, Star Martin, near the town of Krupka, is located about one kilometer north of this sampling site and at higher elevation (Figure 1). Breiter et al. (Breiter et al., 2017) mapped Krupka as a hidden stock of post caldera zinnwaldite granites. The proximity of this granite stock and the drainage to this underground shaft could be causing the very high concentrations of Li and F-, which are higher than water sampled within the actual Cnovec mine (CMine). At the Homolka site, the three samples most enriched in Li  H3, H4, and H7 (label hidden below H4)  all came from small streams (< 1.0 m wide) directly within the deposit itself (Fig. A2). Not all small streams within the deposit were significantly enriched in Li, however (e.g., H1, H2), although most do plot above at least 0.01 mg/L (e.g., H5,


above at least 0.01 mg/L (e.g., H5, H6, H8). Samples H12 and H13 are from a catchment area in which there are no outcrops of the Homolka granite, and plot at background values (0.006 mg/L). Because two of the three downstream samples (H11, H14) did not show elevated Li concentrations, there seems to exist some Li-removal process(es) further downstream, possibly via uptake by vegetation and/or clay adsorption ((Aral and Vecchio-Sadus, 2008)), or via precipitation of known, natural Li compounds with low solubilities, such as Li-fluoride, -phosphate, or -carbonate (Kavanagh et al., 2017). Alternatively, dilution by mixing with water from other drainage areas could also explain the lower Li concentrations in the downstream samples. In fact, dilution may have a considerable effect on ion concentrations. In another study, for example, significant impacts on the concentrations of Fe, Cu, Zn, and Co due to dilution have been


Zn, and Co due to dilution have been observed only 300 meters away from the point source of these elements (Moon, 1999). The magnitude of dilution can be approximated by analyzing stream sediment and taking into account the catchment area of the stream (Moon, 1999). This approach, however, was beyond the scope of our study but might provide valuable insights in a future investigation.


Inverse geochemical modeling showed that the evolution of water chemistry from rainwater to streamflow samples can be accounted for by dissolving zinnwaldite, fluorite, biotite, gypsum, halite (dry deposition) and CO2, and precipitation of Al-Si phases such as allophane and kaolinite. The decrease of Li in downstream samples was modelled as ion-exchange reactions involving Li species. This approach presents an uncertainty, and, in the future, lithium isotope analysis could represent another constraint to interpreting the lower Li concentrations in downstream samples.


Weathering and associated Li behavior in river basins have been studied increasingly by using Li isotopes as a proxy for silicate weathering (Penniston-Dorland et al., 2017; Tomascak, 2004; Tomascak et al., 2016; von Strandmann et al., 2020). Typically, congruent weathering (primary mineral dissolution without significant secondary mineral precipitation, (Dellinger et al., 2015)) takes place upstream and leads to larger concentrations of aqueous Li and isotopically light waters (i.e., low 7Li values), similar to the parent rock material (von Strandmann et al., 2020). Further downstream, where secondary mineral precipitation is significant, weathering is termed incongruent and Li concentrations tend to be lower because Li is removed from solution by incorporation into the crystal structure and/or the exchangeable layer of clays (von Strandmann et al., 2020). Accommodation of Li in the exchangeable layer does not lead to much isotopic fractionation, but the Li that is incorporated into the octahedral site of the clays is preferentially the lighter 6Li, leaving the waters enriched in 7Li (Dellinger et al., 2015; Tomascak et al., 2016; von Strandmann et al., 2020). Studying the isotopic composition of our aqueous samples in the future would allow us to evaluate whether the lower Li concentrations downstream are due to clay precipitation (high 7Li) or due to dilution (similar 7Li as upstream).


Near the Cnovec site, higher Li concentrations were observed in samples collected closer to the deposit than further downstream, likely pointing to dilution or the mentioned Li-removal processes. Other sites showed no upstream/downstream distinction. Low concentrations of both Li and F- at the Podles site could be explained by the physical size of the Li-enriched granite bodies  their area is relatively small compared to the watershed sampled and, thus, dilution could be effective at lowering the concentration. In the Sankt Radegund bei Graz site, similarly, the pegmatite outcrops are likely too small to have a major impact on the chemical composition of the surface water. The SE Ireland pegmatites form a long chain of pegmatite outcrops (Kavanagh et al., 2017), likely having a larger impact on the local aqueous geochemistry. The samples from the Gonalo mine in Portugal were collected within an active mining area and in a landscape dominated by Li-aplite-pegmatite-sills (Rodrigues et al., 2019), also likely having larger impact on the water geochemistry as a result of the larger area covered. The dominant signature of Mg2+, Ca2+, and HCO3- in the Sankt Radegund waters most likely reflect the weathering of the marble/dolomite Schckelkalk Formation, as indicated by the arithmetic mean SIs for calcite and dolomite, which are near equilibrium (-0.52 and -0.60, respectively) for these waters.


Lithium is strongly correlated with F- in the three Li-mica deposits, albeit not significantly in the Podles site (Table 3, Figure 4). The strong correlations point to these elements being leached from the same minerals, which would be the Li-micas. The slopes of the F- vs. Li linear regression lines for the Podles and Homolka waters are similar (~3). We would expect the slope to be around 2 if all F- were derived from the micas, based on the theoretical KLiFeAl2Si3O10F2 composition of the model zinnwaldite (see equation (1)). The Cnovec correlation coefficient is comparable to Homolkas (0.679 and 0.701, respectively), but the slope of the correlation line is an order of magnitude larger for the Cnovec data (Fig. 4). This result implies dissolution of an additional F-bearing phase. The water composition at site C12 is an outlier among the Cnovec samples, likely because it represents drainage from a fluorite-rich and


it represents drainage from a fluorite-rich and zinnwaldite-poor vein. Fluorite, and possibly fluorapatite, are the only other minerals in the area that contain F (Breiter et al., 2017) and both are undersaturated at the C12 site (Figure 5). Based on four out of five minimal inverse models (Table 4), the C12 site is most likely explained by near exclusive fluorite dissolution (i.e., very little zinnwaldite); the remaining model (Model 4) predicts fluorite and zinnwaldite to dissolve in comparable amounts, which would require the Li supplied by the zinnwaldite dissolution to be scrubbed by clay minerals, which would be kaolinite in this specific model. At the C14 site, both inverse models explain the excess F- as produced by dissolving six-times more fluorite than zinnwaldite. At the CMine site, the excess F- is due to exclusive dissolution of zinnwaldite, or alternatively, it is caused by dissolution of equal amounts of fluorite and


by dissolution of equal amounts of fluorite and zinnwaldite. No model for any site requires apatite to dissolve or to precipitate, even though it is thermodynamically undersaturated in C12 and oversaturated in C14 (Figure 5). If our inverse modeling results were correct, it would appear that each site is quite different and it is difficult to state conclusively whether zinnwaldite or fluorite are the main phases supplying F-, as the inverse models point in different directions at the different sites. It does appear, however, that fluorite dissolution is more important at sites C14 and C12, whereas zinnwaldite dissolution is more important at the CMine site. A dissolution experiment of the rocks would allow for a better explanation in regard to which minerals are providing the ions we observed in the water, as it would take into account the actual geochemical concentrations in the rock, mineral makeup, kinetics, as well as thermodynamics. We are currently working on such an experiment.


Lithium also correlates strongly with Al and Si (Table 2), the core building blocks of the mica structure, although only one Si (Homolka) and two Al (Cnovec and Homolka) correlations are significant. While the Si vs. Li correlation is very strong and significant at the Homolka site, the slope of the line approaches 100, i.e., most of the silicon is derived from other sources. At Cnovec and Homolka, the slopes of the Al vs. Li regression lines are ~16 and ~14, respectively, suggesting significant release of aluminum from minerals other than the Li-micas, most likely the feldspars or biotite, also suggested by the nearly identical K vs. Li regression line slope in Cnovec of ~15. The strong and significant Si vs. Al regression in Homolka yields a slope of ~4.5, above the expected value for pure feldspar dissolution (~3), suggesting significant input from the micas. Even though Fe is present in zinnwaldite, it does not


Fe is present in zinnwaldite, it does not correlate with Li at any of the sites (Tables A2-A5). Therefore, Fe is likely derived from more common Fe-bearing minerals, such as biotite (predicted to dissolve, for example, at all modelled Cnovec sites; see Table 4), or hematite, which is present in minor amounts in the pink-colored granites. We analyzed the correlation between Mg and Li in view of their nearly identical ionic radii (0.72  and 0.74 , respectively). In Li-brine processing, it is generally difficult to separate Li+ from Mg2+, and as a result, brines with large molar Mg/Li values are not being considered economical Li-sources (Ogawa et al., 2014). The arithmetic mean Mg/Li molar values in Cnovec waters are 69.7, in Homolka 33.0, in Podles 91.5, and in Sankt Radegund 167.7. The seawater Mg/Li value is 7000, which is the major reason why seawater is


which is the major reason why seawater is currently not a source of Li. The molar Mg/Li value of the Great Salt Lake, which is currently being explored as a potential source of Li (Marthi and Smith, 2019), is 133.33, whereas it is 6.6 for the Salar de Atacama, the most productive, albeit not the largest, brine deposit (Kavanagh et al., 2018). The relatively low Mg/Li values of the waters studied here suggest it might be feasible to recover leached Li from the waterways or tailing ponds around hard-rock deposits, especially should the concentration of Li increase as a result of mining operations. Both elements also tend to be incorporated into the clay interlayer or precipitate as part of secondary minerals during incongruent weathering (von Strandmann et al., 2020; Wimpenny et al., 2014), suggesting that perhaps it is this process that leads to the strong correlation (Table 3) rather than primary mineral dissolution. Clay uptake may also be why


dissolution. Clay uptake may also be why the highest Li concentrations reported in the current Czech waters are found near sediment deposits (Chuman et al., 2013). We see a strong positive correlation between Mg and Li at the Cnovec site and a comparably strong negative correlation between these species at the Podles site. While we cannot say much about clay precipitation/uptake of ions without sequential extraction of the sediment/clay minerals or without a Li-isotope study (Li-isotope fractionation most pronounced during secondary mineral formation (von Strandmann et al., 2020)), our inverse models do suggest significant Li removal from solution via clay adsorption and/or precipitation. Our models only consider ion-exchange as we do not have data on how much Li is/would be present in the clays in our study area, which would allow us to model the Li removed from solution by clay precipitation. The best approach to studying the ratio of how much Li is in the exchangeable site compared to the octahedral site


the exchangeable site compared to the octahedral site of the clays in our samples would be via determination of Li isotopic compositions (von Strandmann et al., 2020). Either process (clay precipitation or adsorption) would explain why we find highly Li-concentrated samples near the deposits and low Li concentrations in downstream waters. This lends itself to a future investigation assessing the Li movement in these environments. Adsorption of Li onto clays, as documented in experiments (up to 99% of Li scrubbed by kaolinite in laboratory conditions within 1000 minutes of the experiment, (Li and Liu, 2020)), points to a potential remediation technique for high-Li waters under natural conditions. This method would also work better in lower-Mg/Li waters, as there would be less competition between the ions. We also examined the phosphate correlations due to the presence of amblygonite and fluorapatite at the Podles site, and indeed, there is a strong and significant positive correlation between F- and phosphate at


and significant positive correlation between F- and phosphate at this location. On the other hand, we also observed a relatively strong correlation between F- and phosphate (not significant, however) in the Sankt Radegund bei Graz deposit where no F- or phosphate-bearing minerals have been identified. No strong correlation between Li and phosphate is found at any of the studied sites (Tables A2-A5). Finally, there are several very strong and significant correlations in the Cnovec site, mostly involving Cl-, Na, K, Mg (Table A2). Those are presented as additional clues into the environment examined and could prove important to future investigations of similar deposits, but these strong correlations are much fewer in number at our other studied locations. Lithium correlates very strongly with some of these ions in the Cnovec waters as well (e.g., Ca, Cl-, K). Our inverse modeling results suggest that these correlations could be the result of clay interaction, as Li, Ca, K, and Na are all affected by


Li, Ca, K, and Na are all affected by clay adsorption/precipitation. It is further important to note that some of these correlations, especially between Si, Al, and Mg, may be an artifact of not filtering the water samples and introducing contributions of microminerals from the areas examined.


### 5. Conclusions
Weathering of Li-mica deposits can result in elevated Li and F- levels in the surface waters in close proximity to these deposits. The most important characteristics impacting the surface water chemistry appear to be: 1) Li and F contents of the rocks; 2) presence or absence of accessory fluorite; 3) the size of the Li-rich granite body relative to the drainage area; and 4) how close to the surface a given Li-rich granite is to have an impact on surface waters. In the case of the studied Cnovec deposit, markedly high F- levels have been observed, which are likely a product of fluorite and zinnwaldite dissolution, depending on the exact site and rock type being drained. The amount of F- present in three of the ten Cnovec samples is considerably above the WHO drinking water limit and represents a public health risk. This risk could be heightened by the development and mining of this deposit as more of these Li- and F-rich rocks would be exposed to the atmosphere, which would result in weathering. However, Li-ores with no or only minimal fluorite may not result in the increased leaching of F- into the waterways, as suggested by our statistical and geochemical modeling work. Dissolution experiments should be carried out on the leaching of Li and F from these rocks to confirm our prediction and pinpoint which mineral is most responsible for the F- input. The Li concentrations in five of the samples analyzed here are above those of average surface waters around the world, but not as high as in two spodumene deposits examined in other studies, likely due to clay uptake of the Li. The measured Li concentrations in waters around the studied Li deposits do not currently pose a public health threat based on the EPA-recommended Li concentration in drinking water.


#### Funding:
This research was funded in part by the Water Center at Penn Student Support Program.
#### Acknowledgments:
For guidance early in the conceptualization phase and suggestion of field sites, we thank Dr. Karel Breiter. We also thank Dr. Rainer Sennewald for access to the old Zinnwald tin mine, his insights on local geology, and assistance with sampling. Finally, we thank the two anonymous reviewers for their invaluable feedback and editor Dr. Stefano Albanese for handling our manuscript.
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Althia Exterminator of Destiny

# Althia Exterminator of Destiny
---

# - Inner Demon -
---

There is something beautiful about watching the world burn. The flames dance and flicker, and the screams of the dying are like music to my ears. The chaos is a thing of beauty, a symphony of destruction that I have composed.

I know that others may see me as evil, but to me, it's just the way of things. The strong will always prey on the weak, and the world is full of weaklings who are too afraid to take what they want. I am not afraid. I will take what I want, and I will destroy anyone who stands in my way.

I imagine the chaos that would ensue if I were to set fire to everything I see. The screams of terrified people would be music to my ears. I can almost taste the smoke and feel the heat on my skin. This is my true calling, and nothing can stand in my way.

But then, a small voice whispers in the back of my mind. It's the other half of me, the one that wants to do good in the world. It tells me that what I am planning is wrong, that innocent people will be hurt. I try to silence the voice, but it persists, urging me to reconsider.

I am torn between these two conflicting parts of myself. One wants to bring about destruction and chaos, while the other wants to prevent it. But deep down, I know which side I truly belong to. The darkness within me is too strong to ignore.

I embrace my villainous persona once again, reveling in the thought of the world burning at my feet.


Necromancer Black Goat of the Event Horizon

The antagonist to the story of Hestia, he was once a student of the Halls of the Hallowed. Soon after he started studying there, he felt his interest being piqued by the darker elements of alchemy, the ones that were hidden away by the other scholars. There was a reason for that knowledge to be forbidden. Since the dawn of man, mankind has had the audacity to challenge the laws of nature, almost always resulting in arcane knowledge that would take away from the balance of life instead of searching for ways to better it. After his departure from the Halls of Hallowed, he started to amass wealth, knowledge and an army of undead behind his cause.
By the time he made himself known to the masses, he was transformed beyond recognition, no longer the frail student at the Halls trying to experiment but rather a formidable opponent of the forces of good. He now stands once more face to face against Hestia, the only one who recognised the person behind the Necromancer, behind his altered appearance and behind his new name as Black Goat of the Event Horizon. The things the Necromancer has gathered in his period of disappearance are the artifacts of legends and tales, and a closer look is needed to understand the amassed power of the Necromancer.


The first adventure he undertook to found ancient relics was to find an artifact of the fabled arcane user Merlin. Merlin is often seen as the founder of the Halls of the Hallowed, although no one has ever proven the mythical arcanist ever roamed the continent for real. But the Necromancer did. In ancient scrolls he found the location of Merlins crypt. He emerged from the crypt victorious and gained a new ally in his fight against the forces of light. At first, it would seem that Merlins Monkey was an ordinary animal but he has been reanimated by the Necromancer, and in his brain reside the memories of Merlins experiments and research, something the Necromancer uses frequently to further his understanding of the arcane arts. The monkey itself is also a quick and vicious foe in battle, fighting from the shoulder of his master or jumping from enemy to enemy and clawing away at their throats or eyes.


After this, he needed more power for himself. He started experimenting with magic that would alter himself in return for dark secrets. Once the Necromancer had a regular face, some would have even called him handsome in the day. Not anymore. Forbidden magic and dark arts come with a price, and one of the first ones the Necromancer had to pay was his face. Slowly but surely with each experiment and each grab for power his head became less and less human and shifted to something supernatural. Now, his face represents the dark and ancient demons he prays to and summons to gather their strength. With horns and a long face, the goat-like appearance has replaced his head fully. His red piercing eyes are alleged mirrors of hell, giving each unprotected person who looks into them the feeling they have stared into the abyss. These people will be haunted with visions and nightmares for the rest of their lives.
Even with the payoff of his face and his human-like traits, the Necromancer would argue that he gained more than he lost. Because he gave up his own head for the demonic variant he now possesses, he has gained the ability of breathing death all around him. The story goes that he tricked the demons from below in giving him the abilities of their hunter-gatherer on the mortal plane, the Grim Reaper. This creature is supposed to be the one that collects the souls of people who are destined to die and bring them to hell.


But now, this power is wielded by the Necromancer. He doesnt send their souls to hell however, instead opting to place them in purgatory, between the living and death, granting him life force from them to gain more powers for himself. Already a few powers under his belt, he felt like he still needed more. Each alchemist or mage in the world one day dreams of discovering a new fundamental understanding of the arcane arts, but few succeed. The Necromancer has done this shortly after leaving the Halls of the Hallowed destroyed. In his search for endless power, he had stumbled upon the grimoire of a dark wizard of centuries ago. In there, he found the beginnings of a spell, and over the course of three years, he has perfected it.
Now he wields the power of the Death spell. Where the Grim reapers breath is used in close contact with people, the Death spell can be used to kill several people at once even from a far distance. Alchemists and mages have found ways to conceal themselves or others from this spell, but these protections arent for anybody. Because of this, the Necromancer is able to take out opponents even before the conflict reaches a combat stage. Finally, he found himself powerful enough that he just needed one thing more, a rune.


The runes of the elements are one of the strangest elemental forces in the universe. Each of the four elements has a rune, a mystical key that can be unlocked by experienced alchemists and mages to add an extra layer to their powers. The Necromancer has opted to wield the power of the Rune of Water. This is another sign of his intelligence. More impulsive or aggressive enchanters opt for the Runes of earth or fire, both having more of a visual element to their danger. Instead the Rune of Water is calm and eternal. It turns earth into clay and mud, rendering it ineffective, it douses fire and destroys it and air cannot touch the water without becoming part of it. Because of this, by wielding the power of the Rune of water, the Necromancer has positioned himself in the most advantageous position against other wielders of Runes.


Milo of the Wood

### The Epic Tale of
# The Green Wizard Milo and the Goblet of Immortality

```

In Runiverse, where stars did shine,
A wizard green as the forest pine
Milo of the Wood, he was known
With bright green eyes, hat and cape shown
And a goblet, a prize for deeds most fine

A dragon fierce, in the Hall of Cats
Did threaten all, with fiery spats
But Milo, brave and true
Fought with might and virtue
And saved the hall, with dragon bane cats

The goblet, a reward for his deeds
Immortality, it did cede
A powerful tool, in his hand
With it, his magic did expand
His foes, by its power, were led

Through the land, he did roam
Battling foes, throughout his wooded home
His power, it did grow
As he faced every foe
His legend, in song and tale, did expand

But with power, came great responsibility
For immortality, his soul was the fee
He used it wisely and well
For good deeds, and feats for sale
Milo of the Wood, his name echoes still in history.


Magus Lamia of the Field

# New Lore Entry

In a land far away, beyond the rolling hills and endless green fields, there lived a female wizard named Magus Lamia of the Field. She was known far and wide for her mastery of the arcane arts and her affiliation with the Purple Haze, a mysterious order of magic-users who drew their power from the pulsating hues of the aurora borealis. Magus Lamia was a striking figure, always clad in flowing purple Yoga clothes, and with flowers of every color adorning her hair. Her constant companion was a sleek black cat, who brought her good fortune wherever she went.

Despite her imposing reputation, Magus Lamia was a kind and gentle soul, with a love for all living things. She would spend hours tending to the plants and animals that called the Field their home, and her gardens were renowned for their vibrant colors and sweet fragrances. But when danger threatened, Magus Lamia would draw upon her magical powers to defend her beloved home. Her signature move was the Dragon Firework, a spell that would send a cascade of glittering sparks raining down upon her enemies, leaving them dazzled and disoriented.

Magus Lamia was never without her special Rune of Brass, a powerful talisman that had been passed down to her by her ancestors. It glowed with a warm golden light, and was said to be imbued with the wisdom of the ages. With its aid, Magus Lamia could unlock secrets and mysteries that were hidden to others, and navigate the most treacherous paths with ease. And so she lived, a solitary figure in the Field, but with the power to shape the very fabric of the world around her.


Eidolon of Concrete

# New Lore Entry

Once upon a time, in a land far away, there lived a fierce warrior named Eidolon of Concrete. He was known throughout the land for his bravery, his love of the desert, and his distinctive fashion sense. Eidolon wore a purple wrestling singlet that showed off his muscular arms and legs, and an indigo Mendicant that billowed in the wind as he rode his horse across the sands. But most impressive of all was the rapier he carried, a sword that glinted in the sun and could cut through stone with ease.

Eidolon's fame as a warrior grew with each passing day, as he battled fierce beasts and protected his people from marauding bandits. But one day, a new threat emerged from the desert: a band of ruthless raiders who threatened to destroy everything Eidolon held dear. With his trusty rapier in hand, Eidolon rode out to meet the enemy, his heart filled with determination and his mind focused on victory.

For days on end, Eidolon and his men fought against the raiders, never giving up despite their overwhelming numbers. And in the end, it was Eidolon's skill with his rapier that saved the day. With a swift and precise stroke, he cut down the raiders' leader, causing the rest of the band to flee in terror. And thus, Eidolon of Concrete became a hero in the eyes of his people, a symbol of hope and strength in a world filled with darkness and danger.


Magus Jabir of the Oasis

# Magus Jabir of the Oasis #2652

_Lore of a stranger who came out of the sand_

Hardly anything is known about the old traditions today. Above all, little is known about the sub-cult of the Foreign Mages from the Sandlands.

### Traditions & identifying characteristics of the sub-cult.

Beside practical reasons, you will never find out what kind of face is hidden behind the face towel of a Sandland Magus, only the fiery glowing eyes are freely visible.
They usually wear fine, silky fabrics. As well as imposing magic hats, which are also practical especially when the sun is burning.

## Rumors about Magus Jabir "of the Oasis"
_The Stranger from the sands, known as the Eye of the Desert_

*Magus Jabir* is mainly found in the region around the > Zaros Oasis. But watch out, he sees you long before you would notice.
He possesses one of the rare and powerful Orb Staves. The orb of an orbital fragment of bygone times and worlds , grants channeling magic to its wielder. He can use it to form a desert eye that carries his spirit across the dunes and spy everything that doesn't have sand in its heart & soul.

Pssst he is said to be accompanied by an psychic rabbit, which is said to be poisonous. Caution is advised!

Also not to be forgotten is that he carries the *Rune of Water *. He will always find a way to survive in the desert, the oases calling his name as he listens to the wind in the sandlands.


> There's only one other sub-cult that might know more about the strangers from the sands. Few know about
  the entanglements of the Green Mages and those who seem lost in the sand. Who knows what can be found
  in the secret writings in the green tower, deep in the forest in > Green Wizard City.

I keep searching, I'll reveal the scriptures and figure out the context..My journey will only end, if I
  get lost along the way.
> *luckyno7.eth*


Ice Mage Nori of the Expanse

#  A Gift to Penguin Capital

My supply of fish was running low, so I traveled to Penguin Capital today. As youd expect, it's a city in the north largely populated by penguins and their allies. It's located in an area central to The Snow, The Expanse, and The Tundra, making it easy to travel between these areas; which are sectioned off by large mountains and ice water.

It was built long ago with the help of ice mages who sought to protect the feathery critters who were almost hunted to extinction. Penguins had to be strong to survive, especially from the dangerous predators in The Tundra like frost gnomes, yetis, and abominable snow mimics. Now it flourishes as a convenient resting point for those willing to travel throughout the northern region as its central point between key regions of the north benefits friends of the Penguins with easier transport. The mountains surrounding it make for great natural walls, with tunnels carved through them that are heavily guarded for safe commuting in and out of the city.

It is a city of contrasts, with stark white buildings and dark shadows cast by the towering mountains that surround it. The streets are slick with ice, and the chill in the air is palpable. Despite the harsh environment, the streets are bustling with activity, as penguins and their allies hurry about their daily business.

I sent my trusty owl Mochi with a message to @warrior15502 who lives within, so she could prepare for my arrival. She's somewhat treated as a princess to the Penguins, but as far as I can tell she doesn't care about the clout, just loves all the fish they shower her with in gratitude for her protection. Building a relationship with her was highly beneficial, as she always has a surplus of exotic fish to trade and share.


But on the way there, while crossing through The Snow, I spotted a pirate ship which was stranded on expansive snowy white land... far away from any liquid bodies of water.

It was a creaky old vessel, manned by a group of rugged sailors. They were working hard to get the ship back in shape, patching the holes in the hull and replacing the broken ropes. The decks were cluttered with tools and debris, and the sailors were shouting orders to each other. The ship's figurehead, a mermaid with a crown and sword, was missing an arm, and her face was twisted in a grotesque grimace.

It seems that the pirate crew had made a grave mistake in navigation while en route to Donut Atoll in search of the elusive "Jellybeard's Treasure." Whatever that is. They encountered a vicious Strawberry Shortcake Kraken. Ive never heard of it before, so I have no clue if they were exaggerating their description or not. According to the crew, the krakens massive body is covered in thick, pink and red striped tentacles that are adorned with sugary-looking pink and white swirls. Its eyes are large and round, with a bright red iris, speckled with white spots that looked like seeds, giving it a menacing yet playful appearance. It's known for its mischievous and playful nature, but it should not be underestimated as it can be quite dangerous when it feels threatened.

The creature lifted their ship and sent it hurtling across the land and sea, landing them far north in the Tundra. Despite the severity of the incident, it was nothing short of a miracle that the ship managed to land in one piece. The softness of the landing was a clear indication that some form of Aeromancy had been used to cushion the fall.


As I approached the ship, I was filled with hope, as I thought I might be able to trade for something valuable. However, it was clear that the crew was only on this quest because they were painfully poor and banking hard on the treasure to ease their financial troubles. How unlucky for them to be thrown this far. Okay actually, it's somewhat hilarious but I'll hold back my laughter for their sake."

Still, they were in need of a map since their lack of one was how they got lost in the first place. If they didn't know where they were before, there's no way there'd know where they are now. Of course I happen to carry a few with me, since it's not unlikely you'll find a lost traveler in these parts, but I don't run a charity so they had to negotiate for it.

As I climbed aboard the rickety pirate ship, I couldn't help but feel a sense of disappointment at the state of the vessel. The ship was in a shoddy condition and seemed to be devoid of anything valuable. The cheap wooden utensils and plates, the pungent smell of cheap beer and wine, and the moldy cheese that seemed barely edible, Its no wonder the crew was in dire need of treasure just to pay off their bills. But as I was about to give up on finding any valuable items, my eyes caught sight of a bundle of fishing poles stacked neatly in a corner of the main deck. It was an unexpected find, but it seemed the crew had a hobby for fishing, and it was something that caught my interest.


Cant imagine being a pirate and disliking fish. Well I happen to know some professional fishers myself who would probably make good use of those. I asked for half their stock of fishing poles in exchange for my map. Of course the deal was clearly in my favor, but their only other option was to remain lost in the north for who knows how long haha. They didn't like it, but they had no choice but to accept the deal. I heard one of the wizards grumble under his breath that they'll never be able to convince the Nightmare Imp for more. They should be fine with the poles they still have left, they're not going to starve or anything... as long as they don't break any along the way back. I gave them some brief instructions on how to get back at sea, winked for luck, and left their ship to continue on the road to Penguin Capital. It's not every day that I have such a chance encounter with a good deal, so I felt pretty lucky keeping that momentum going and negotiating a storm at the capital. Wait, do I want a storm? Yes.

_______________


_______________

Two large Battle Penguins stood in front of the west gates into the capital. As I approached they puffed out their chests to look more intimidating...how cute lol. But it only took a moment for them to recognize me. Normally you'd need a special identification pass to enter the capital, but I visit so often that I pretty much never need to show it. The guards recognized me, and quickly waddled over to a large drum that rested alongside the gate. One of them took out a pair of fish bones from somewhere under his belly feathers and began beating on it. They always try acting so tough, but I always end up clapping when they do this because it feels like a circus performance. One of the guards turned back to me and took a bow, as the gates opened behind them. The other guard, looking a bit annoyed, nudged his partner in the side. Probably to remind him that they're on duty. They both looked a bit embarrassed but I can't help humoring them when they're this adorable. With a backpack filled with fishing rods, I made my way through the gates and into the capital.

As expected, the capital is filled with Penguins waddling and sliding around the snowy town mostly consisting of igloos and other buildings made entirely of ice. Being fortified by ice magic, all of those structures are certain to be stronger than the average brick building. Beautiful snowbell flowers decorated the town around every corner, they seem to be a favorite for the penguins, probably because of the soothing sounds they emit during heavy snowfall.