# Minerals/Pnictogens

Def. any "element from group 15 of the periodic table; nitrogen, phosphorus, arsenic, antimony and bismuth" is called a pnictogen.
Some of the pnictogens like phosphorus, arsenic, antimony and bismuth, occur as metalloids.
Arsenopyrite on the right is 33.3 at % arsenic.

## Nitrogens

The only important nitrogen minerals are nitre (potassium nitrate, saltpetre) and sodanitre (sodium nitrate, Chilean saltpetre).

## Ammoniacal nitrogens

Ammoniacal nitrogen (NH$_3$-N) is a measure for the amount of ammonia, a toxic pollutant often found in landfill leachate and in waste products, such as sewage, liquid manure and other liquid organic waste products. It can also be used as a measure of the health of water in natural bodies such as rivers or lakes, or in man made water reservoirs.
The typical output of liquid manure from a dairy farm, after separation from the solids is 1600 mg NH$_3$-N /L. Sewage treatment plants, receiving lower values, typically remove 80% and more of input ammonia and reach NH$_3$-N values of 250 mg/L or less.

## Nitrides

A nitride mineral is a compound of nitrogen that occurs as a mineral where nitrogen has a formal oxidation state of −3 with a wide range of properties.

## Carlsbergites

Carlsbergite was first described in the Agpalilik fragment of the Cape York meteorite.
It is a chromium nitride mineral (CrN), named after the Carlsberg Foundation that backed the recovery of the Agpalilik fragment from the Cape York meteorite.
It occurs in meteorites along the grain boundaries of kamacite or troilite in the form of tiny plates, associated with kamacite, taenite, daubreelite, troilite and sphalerite.
In addition to the Cape York meteorite, carlsbergite has been reported from:
* the North Chile meteorite in the Antofagasta Province, Chile
* the Nentmannsdorf meteorite of Bahretal, Erzgebirge, Saxony
* the Okinawa Trough, Senkaku Islands, Okinawa Prefecture, Japan
* the Uwet meteorite of Cross River State, Nigeria
* the Sikhote-Alin meteorite, Sikhote-Alin Mountains, Russia
* the Hex River Mountains meteorite from the Cape Winelands District, Western Cape Province, South Africa
* the Canyon Diablo meteorite of Meteor Crater, Coconino County, Arizona
* the Smithonia meteorite of Oglethorpe County, Georgia
* the Kenton County meteorite of Kenton County, Kentucky
* the Lombard meteorite of Broadwater County, Montana
* the Murphy meteorite of Cherokee County and the Lick Creek meteorite of Davidson County, North Carolina
* the New Baltimore meteorite of Somerset County, Pennsylvania

## Osbornites

Osbornite is a very rare natural form of titanium nitride (TiN), found almost exclusively in meteorites.

## Qingsongites

Qingsongite is a rare boron nitride (BN) mineral with cubic crystalline form first described in 2009 for an occurrence as minute inclusions within chromite deposits in the Luobusa ophiolite in the Shannan Prefecture, Tibet Autonomous Region, China. It was recognized as a mineral in August 2013 by the International Mineralogical Association named after Chinese geologist Qingsong Fang (1939–2010). Qingsongite is the only known boron mineral that is formed deep in the Earth's mantle. Associated minerals or phases include osbornite (titanium nitride), coesite, kyanite and amorphous carbon.

## Nitrites

Davinciite was discovered in hyperagpaitic (highly alkaline) pegmatite at Mt. Rasvmuchorr, Khibiny massif, Kola Peninsula, Russia, with associated minerals aegirine, delhayelite, nepheline, potassium feldspar, shcherbakovite, sodalite (silicates), djerfisherite, rasvumite (sulfides), nitrite, nacaphite, and villiaumite.

## Nitrates

Nitrate is a polyatomic ion with the molecular formula NO$^−$ $_3$ and a molecular mass of 62.0049 unified atomic mass units (u).

## Gwihabaites

Gwihabaite [(NH$_4$), K]NO$_3$ is from Gcwihaba Cave, Botswana.
K by XRF, N and H by gas chromatography, original total reported as 98.90%; corresponds to [(NH$_4$)$_{0.81}$)K$_{0.19}$]$_{Σ=1.00}$(NO$_3$)$_{1.00}$.

## Phosphoruses

"Elemental phosphorus can exist in several allotropes; the most common of which are white and red solids. Solid violet and black allotropes are also known."
"It would appear that violet phosphorus is a polymer of high relative molecular mass, which on heating breaks down into P$_2$ molecules. On cooling, these would normally dimerize to give P$_4$ molecules (i.e. white phosphorus) but, in vacuo, they link up again to form the polymeric violet allotrope."

## Phosphides

A phosphide mineral is a compound containing the P$^{3−}$ ion or its equivalent occurring naturally with many different phosphides known, and widely differing structures.

## Schreibersites

Schreibersite is generally a rare iron nickel phosphide mineral, (Fe,Ni)$_3$P, though common in iron-nickel meteorites, where the only known occurrence of the mineral on Earth is located on Disko Island in Greenland.
Another name used for the mineral is rhabdite that forms tetragonal crystals with perfect 001 cleavage; color ranges from bronze to brass yellow to silver white; density is 7.5 and a hardness of 6.5 – 7; opaque with a metallic luster and a dark gray streak; named after the Austrian scientist Carl Franz Anton Ritter von Schreibers (1775–1852), who was one of the first to describe it from iron meteorites.
Schreibersite is reported from the Magura Meteorite, Arva-(present name – Orava), Slovak Republic; the Sikhote-Alin Meteorite in eastern Russia; the São Julião de Moreira Meteorite, Viana do Castelo, Portugal; the Gebel Kamil (meteorite) in Egypt; and numerous other locations including the Moon.
Schreibersite and other meteoric phosphorus bearing minerals may be the ultimate source for the phosphorus that is so important for life on Earth. Pyrophosphite is a possible precursor to pyrophosphate, the molecule associated with adenosine triphosphate (ATP), a co-enzyme central to energy metabolism in all life on Earth, produced by subjecting a sample of schreibersite to a warm, acidic environment typically found in association with volcanic activity, activity that was far more common on the primordial Earth, possibly representing "chemical life", a stage of evolution which may have led to the emergence of fully biological life as exists today.

## Phosphates

Phosphate minerals are those that contain the tetrahedrally coordinated phosphate (PO$_4$$^{3−}$) anion along with the freely substituting arsenate (AsO$_4$$^{3−}$) and vanadate (VO$_4$$^{3−}$); chlorine (Cl$^−$), fluorine (F$^−$), and hydroxide (OH$^−$) anions that also fit into the crystal structure.
Phosphate minerals include:
* Triphylite Li(Fe,Mn)PO$_4$
* Monazite (La, Y, Nd, Sm, Gd, Ce, Th)PO$_4$, rare earth metals
* Hinsdalite PbAl$_3$(PO$_4$)(SO$_4$)(OH)$_6$
* Pyromorphite Pb$_5$(PO$_4$)$_3$Cl
* Vanadinite Pb$_5$(VO$_4$)$_3$Cl
* Erythrite Co$_3$(AsO$_4$)$_2$·8H$_2$O
* Amblygonite LiAlPO$_4$F
* lazulite (Mg,Fe)Al$_2$(PO$_4$)$_2$(OH)$_2$
* Wavellite Al$_3$(PO$_4$)$_2$(OH)$_3$·5H$_2$O
* Turquoise CuAl$_6$(PO$_4$)$_4$(OH)$_8$·5H$_2$O
* Autunite Ca(UO$_2$)$_2$(PO$_4$)$_2$·10-12H$_2$O
* Carnotite K$_2$(UO$_2$)$_2$(VO$_4$)$_2$·3H$_2$O
* Phosphophyllite Zn$_2$(Fe,Mn)(PO$_4$)$_2$•4H$_2$O
* Struvite (NH$_4$)MgPO$_4$·6H$_2$O
* Xenotime-Y Y(PO$_4$)
* Apatite group Ca$_5$(PO$_4$)$_3$(F,Cl,OH)
** hydroxylapatite Ca$_5$(PO$_4$)$_3$OH
** fluorapatite Ca$_5$(PO$_4$)$_3$F
** chlorapatite Ca$_5$(PO$_4$)$_3$Cl
** bromapatite Ca$_5$(PO$_4$)$_3$Br
* Mitridatite group:
** Arseniosiderite-mitridatite series (Ca$_2$(Fe$^{3+}$)$_3$[(O)$_2$|(AsO$_4$)$_3$]·3H$_2$O -- Ca$_2$(Fe$^{3+}$)$_3$[(O)$_2$|(PO$_4$)$_3$]·3H$_2$O)
** Arseniosiderite-robertsite series (Ca$_2$(Fe$^{3+}$)$_3$[(O)$_2$|(AsO$_4$)$_3$]·3H$_2$O -- Ca$_3$(Mn$^{3+}$)$_4$[(OH)$_3$|(PO$_4$)$_2$]$_2$·3H$_2$O)

## Apatites

Fluorapatite, a sample of which is shown at right, is a mineral with the formula Ca$_5$(PO$_4$)$_3$F (calcium fluorophosphate) that is the most common phosphate mineral occurring widely as an accessory mineral in igneous rocks, in calcium rich metamorphic rocks, as a detrital or diagenic mineral in sedimentary rocks, is an essential component of phosphorite ore deposits and occurs as a residual mineral in lateritic soils.
At left is another fluorapatite example that is violet in color on quartz crystals.

## Libethenites

Libethenite has the chemical formula Cu $_2$PO $_4$OH, is a rare copper phosphate hydroxide mineral, that forms striking, dark green orthorhombic crystals, discovered in 1823 in Ľubietová, Slovakia, is named after the German name of that locality (Libethen). Libethenite has also been found in the Miguel Vacas Mine, Conceição, Vila Viçosa, Évora District, Portugal, and in Tier des Carrières, Cahai, Vielsaim, Stavelot Massif, Luxembourg Province, Belgium.
Libethenite almost always takes the form of dark-green orthorhombic crystals, often found in clusters with other libethenite crystals.
Libethenite is found in the oxidized zone of copper ore deposits, is most often formed from the weathering of phosphate rocks such as apatite, monazite, and xenotime. There have been no confirmed findings of primary libethenite, although a probable case has been reported.

## Satterlyites

Satterlyite is a hydroxyl bearing iron phosphate mineral. The mineral can be found in phosphatic shales. Satterlyite is part of the phosphate mineral group. Satterlyite is a transparent, light brown to light yellow mineral. Satterlyite has a formula of (Fe$^{2+}$,Mg,Fe$^{3+}$)$_2$(PO$_4$)(OH). Satterlyite occurs in nodules in shale in the Big Fish River (Mandarino, 1978). These nodules were about 10 cm in diameter, some would consist of satterlyite only and others would show satterlyite with quartz, pyrite, wolfeite or maricite.

## Holtedahlites

Holtedahlite, a mineral that was found in Tingelstadtjern quarry in Norway, with the formula (Mg$_{12}$PO$_4$)$_5$(PO$_3$OH,CO$_3$)(OH,O)$_6$ is isostructural with satterlyite (Raade, 1979). Infrared absorption powder spectra show that satterlyite is different than natural holtedahlite in that there is no carbonate for phosphate substitution (Kolitsch, 2002). Satterlyite is also structurally related to phosphoellenbergerite.

## Phosphoellenbergerites

Phosphoellenbergerite is a mineral that was discovered in Modum, Norway; near San Giocomo Vallone Di Gilba, in Western Alps of Italy (Palache, 1951); the minerals formula is Mg$_{14}$(PO$_4$)$_5$(PO$_3$OH)$_2$(OH)$_6$ (Kolitsch, 2002).

## Turquoises

Turquoise at right is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula CuAl$_6$(PO$_4$)$_4$(OH)$_8$·4H$_2$O.

## Arsenics

Native arsenic such as in the image on the right and at the top of this resource occurs in silver ore veins.

## Realgars

Realgar an arsenic sulfide mineral of 1.5-2.5 Mohs hardness is used to make red-orange pigment.
Realgar is a sulfide mineral. But, with equal atomic numbers of sulfur and arsenic, it may act as a pnictide.
This piece on the right is from the less well-known Royal Reward Mine of Washington.

## Arsenates

Arsenates contain AsO $_4$ in their chemical formulas.

## Adamites

Adamite (IMA symbol: Ad) is a zinc arsenate hydroxide mineral, has the chemical formula Zn $_2$AsO $_4$OH, and is a mineral that typically occurs in the oxidized or weathered zone above zinc ore occurrences.
Adamite occurs as a secondary mineral in the oxidized zone of zinc- and arsenic-bearing hydrothermal mineral deposits. It occurs in association with smithsonite, hemimorphite, scorodite, olivenite, calcite, quartz and iron and manganese oxides.

## Adelites

The rare mineral adelite, (IMA symbol Ade) is a calcium, magnesium, arsenate with the chemical formula CaMgAsO $_4$OH, forming a solid solution series with the vanadium-bearing mineral gottlobite, where various transition metals substitute for magnesium and lead replaces calcium leading to a variety of similar minerals in the adelite - duftite group.

## Agardites

Agradite has the chemical formula (REE,Ca)Cu $_6$(AsO $_4$) $_3$(OH) $_6$·3H $_2$O, a repeating unit.
Agardite is a mineral group consisting of agardite-(Y), agardite-(Ce), agardite-(Nd), and agardite-(La). They have been allocated the IMA symbols Agr-Y, Agr-Ce, Agr-Nd and Agr-La. They comprise a group of minerals that are hydrous hydrated arsenates of rare-earth elements (REE) and copper, with the general chemical formula (REE,Ca)Cu $_6$(AsO $_4$) $_3$(OH) $_6$·3H $_2$O. Yttrium, cerium, neodymium, lanthanum, as well as trace to minor amounts of other REEs, are present in their structure. Agardite-(Y) is probably the most often found representative. They form needle-like yellow-green (variably hued) crystals in the hexagonal crystal system. Agardite minerals are a member of the mixite structure group, which has the general chemical formula Cu$^{2+}$ $_6$A(TO $_4$) $_3$(OH) $_6$·3H $_2$O, where A is a REE, Al, Ca, Pb, or Bi, and T is P or As. In addition to the four agardite minerals, the other members of the mixite mineral group are calciopetersite, goudeyite, mixite, petersite-(Ce), petersite-(Y), plumboagardite, and zálesíite.
Agardite-(Y) from the Bou Skour mine in Djebel Sarhro, Morocco was the first of the agardite-group minerals to be characterized. It was described by Dietrich in 1969 and was named after Jules Agard, a French geologist at the Bureau de Recherches Géologiques et Minières, Orléans, France. Agardite-group minerals have subsequently been found in Germany, Czech Republic, Greece, Italy, Japan, Namibia, Poland, Spain, Switzerland, the United Kingdom, and the United States.

## Aheylites

Aheylite (International Mineralogical Association (IMA) symbol: Ahe) is a rare phosphate mineral with formula (Fe$^{2+}$ Zn)Al $_6$[(OH) $_4$(PO $_4$) $_2$] $_2$·4(H $_2$O) that occurs as pale blue to pale green triclinic crystal masses, the newest member of the turquoise group in 1984 by International Mineralogical Association Commission on New Minerals and Mineral Names.
The turquoise group has a basic formula of A $_{(0-1)}$B $_6$(PO $_4$) $_{4−x}$(PO $_3$OH) $_x$(OH) $_8$·4H $_2$O. This group contains six minerals: aheylite, planerite, turquoise, faustite, chalcosiderite, and an unnamed Fe$^{2+}$ -Fe$^{3+}$ analogue. Aheylite is distinguished in this group by having Fe$^{2+}$ dominant in the A-site. The ideal aheylite has a formula of Fe$^{2+}$ Al $_6$(PO $_4$) $_4$(OH) $_8$·4H $_2$O, a pale blue or green. With the turquoise family the blue color is said to come from the octahedral coordination of Cu$^{2+}$ in the absence of Fe$^{3+}$ .
It was first described for an occurrence in the Huanuni mine, Huanuni, Oruro Department, Bolivia, and named for Allen V. Heyl (1918–2008), an economic geologist for the United States Geological Survey. It was discovered by Eugene Foord and Joseph Taggart.
In addition to the type locality in Bolivia it has been reported from the Bali Lo prospect in the Capricorn Range, Western Australia and the Les Montmins Mine, Auvergne, France. It is a turquoise group mineral and occurs as a late hydrothermal phase in a tin deposit associated with variscite, vivianite, wavellite, cassiterite, sphalerite, pyrite and quartz in the type locality.
It is found as an isolated mass of hemispheres and spheres clumped together. It has a vitreous to dull luster. It has a hackly to splintery fracture and it has a brittle tenacity. The hardness is about 5-5.5, and the specific gravity is 2.84. As far as optical properties, it had thin flakes; ipale blue, green to blue-green color; it streaks white, and has a subvitreous luster.

## Olivenites

Olivenite is a copper arsenate mineral has the chemical formula Cu $_2$AsO $_4$OH crystallizes in the monoclinic system (pseudo-orthorhombic), is a mineral of secondary origin, a result of the oxidation of copper ores and arsenopyrite.
The mineral was formerly found in some abundance, associated with limonite and quartz, in the upper workings in the copper mines of the St Day district in Cornwall; also near Redruth, and in the Tintic Mining District in Utah.
The arsenic of olivenite is sometimes partly replaced by a small amount of phosphorus, and in the species libethenite we have the corresponding copper phosphate Cu $_2$PO $_4$OH, found as small dark green crystals resembling olivenite at Ľubietová in the Slovak Republic, and in small amount also in Cornwall. Other members of this isomorphous group of minerals are adamite, Zn $_2$AsO $_4$OH, and eveite, Mn $_2$AsO $_4$OH.

## Allemontites

Allemontite is a native alloy of arsenic and antimony, with a composition of AsSb.
The first example on the right is from the mineral collection of Brigham Young University Department of Geology, Provo, Utah.
The second is from Příbram, Central Bohemia Region, Bohemia (Böhmen; Boehmen), Czech Republic.
As a natural source of arsenic, it has 50 at % arsenic.

## Antimonies

Native antimony such as occurs in the rock on the upper right with its various oxidation products is crystalline in the hexagonal system.
The second image on the left shows hexagonal crystals with metallic luster.

## Bismuths

Bismuth does occur on Earth as native bismuth exampled on the right.

## Bismites

Bismite is a bismuth oxide mineral, bismuth trioxide, or Bi $_2$O $_3$.