Calculated SI values for antigorite and chromite (both not shown) are very positive indicating that the minerals would never dissolve or the thermodynamic data are not very accurate.
Results from the XRD and WDXRF analyses of collected rock and soil samples have shown that major mineral phases found in the area include lizardite, antigorite, calcite, dolomite, and quartz, together with minor amounts of hematite and vermiculite, and trace amounts of clinochlore, magnesite, kaolinite, olivine, chromite, ankerite, dickite, diopside, and phlogopite.
Antigorite (4) reveals the presence of 62.91 wt% SiO2, 24.72 wt% MgO, and minor Fe2O3 (2.59 wt%) and CaO (0.93 wt%).
Locally, retrograde antigorite after forsterite is common.
The planar antigorite seems to exhibit electrokinetic behaviour intermediate between the brucite and silica, indicating equal importance of both the magnesia octahedral sheet (brucite sheet) and the silica tetrahedral sheet.
MD simulations of water at the basal plane surfaces of kaolinite and antigorite performed using DL_POLY_214 software (Smith and Forester, 1996) suggest that the silica tetrahedral face 001 should be hydrophobic, similar to pyrophyllite and talc, see Figure 9.
and Nieto, F.: 1999, The effects of dry grinding on antigorite from Mulhacen, Spain.
and Faust, G.T.: 1956, Serpentines: natural mixtures of chrysotile and antigorite. American Mineralogist, 41, 817-843.
of OR (95% CI) Variables tribes Serpentinite on track Absence 46 1 Presence 34 465.00 (2.360-9, 161) Antigorite
Absence 35 1 Presence 47 20.667 (4.028-106.03) Serpentinite surface (k[m.sup.2]) 0-1.2 27 1 1.21-3 31 13.333 I2.683-66.256) 3.01-30 24 25.000 (4.698-133.03) No.
The olivine (Fo92-94) is partially to completely replaced by antigorite
or occasionally altered to iddingsite.
During the latest stage of Devonian metamorphism, fault-controlled bodies of fibrous and waxy green serpentinite (chrysotile and antigorite
) were formed due to local metasomatism (Peck, 1990).