## 5 Results
### Mineral Chemistry
Chrysotile exhibits low Al\({}_{2}\)O\({}_{3}\) content (1.29-3.79, Figure 6a) and high MgO (43.36-47.35 wt.%) and SiO\({}_{2}\) (44.67-49.35 wt.%) relative to the antigorite phase in serpentinites (4.33-5.66 wt.%; 41.69-45.55 wt.%; 43.18-45.78 wt.%, respectively) and serpentinized periodites (4.55-5.44 wt.%; 41.69-43.77 wt.%; 43.79-45.89 wt.%, respectively), which is consistent with the findings of [33] (Figure 6b-d). The chrysotile phase has a chemical affinity similar to that of olivine, whilst antigorite comes from orthopyroxene and olivine, reflecting a dunite protolith for the former, and both harzburgite and dunite for the latter phase (Figure 6e). The abundance of antigorite rather than chrysotile in the examined ultramafic rocks reflects prograde metamorphism [33; 34]. Chlorite represents one of the main alteration products of the primary minerals (pyroxenes) in serpentinized periodites. EPMA results show that the examined chlorites contain SiO\({}_{2}\) ranges from 33.98 to 37.45 wt.%, Al\({}_{2}\)O\({}_{3}\) from 19.45 to 21.89 wt.%, MgO from 24.62 to 2.45 wt.%, Si from 6.05 to 6.52 apfu, Al\({}^{\rm iv}\) from 1.47 to 1.94 apfu, Fe# from 0.22 to 0.28, and Mg# from 0.72 to 0.78 (Supplementary Materials, Table S6). On the Si (apfu) vs. Fe\({}^{+2}\)+Fe\({}^{+3}\) (apfu) binary diagram [35], the examined chlorite is classified as pyrocholrite and diabantite (Figure 7a). Al\({}^{\rm iv}\) can be used to determine the chlorite temperature [36]. Using the equation in [37] (T = 106.2*Aliv + 17.5), the temperature of chlorite ranges from 174 to 224 \({}^{\circ}\)C.  
Likewise, chlorite and tremolite represent the main alteration products of pyroxene. The examined tremolites (serpentinized peridotites) have SiO\({}_{2}\) ranges from 48.34 to 59.81 wt.%, MgO from 23.33 to 24.71 wt.%, and CaO from 13.17 to 14.63 wt.% (Supplementary Materials, Table S7). They are classified as tremolite according to [40] (Figure 7b). They have Ti contents ranging from 0.003 to 0.014 apfu, with a mean value of 0.0036 apfu, reflecting their metamorphic nature. Furthermore, greenshist facies of the examined rocks are indicated by low Na and K contents of tremolite (av. 0.003 apfu) [41]. The investigated magnetites (serpentinites and serpentinized peridotites) were composed mainly of high FeO* contents (av. 93.76), whilst their TiO\({}_{2}\) (av. 0.055), MnO (av. 0.42), CaO (av. 0.017), Na\({}_{2}\)O (av. 0.027), K\({}_{2}\)O (av. 0.015), Cr\({}_{2}\)O\({}_{3}\) (av. 0.29), NiO (av. 0.18), and ZnO (av. 0.031) contents are less than unity (Supplementary Materials, Table S8). They possess ulvospinel of less than 0.5 mol%, based on [42]. They are classified mainly as magnetites  
Figure 6: Serpentine binary variations: (**a**) MgO vs. Al\({}_{2}\)O\({}_{3}\); (**b**) MgO vs. FeO; (**c**) MgO vs. NiO; (**d**) MgO vs. MnO; and (**e**) Cr\({}_{2}\)O\({}_{3}\) vs. NiO. Fields of antigorite and chrysotile are from [38]; serpentine after olivine and orthopyroxene fields are from [39]. by using the FeO-TiO\({}_{2}\)-Fe\({}_{2}\)O\({}_{3}\) ternary diagram (Figure 7c). In addition, the abundance of magnetites--either as patches, or filling fractures as veinlets--reflects the high degree of alteration of primary minerals, such as olivine [43]. EPMA of the examined talcs reveals that they consist mainly of SiO\({}_{2}\) ranges from 56.35 to 60.99 wt.%, Na\({}_{2}\)O from 12.77 to 15.44 wt.%, Al\({}_{2}\)O\({}_{3}\) from 18.47 to 23.45 wt.%, Mg# from 13.84 to 24.34, K# from 0.001 to 0.015, and Fe# from 75.65 to 86.16 (Supplementary Materials, Table S9). It is widely known that the talc forms as an alteration product after primary minerals (olivine and serpentine), suggesting high-temperature metamorphism.