Geology and Minerals
Cookeite is a mineral species of the silicate group and the phyllosilicate subgroup, part of the chlorite family, with the formula LiAl4(Si3Al)O10(OH)8. This soft, low-density mineral of variable color has a crystalline structure made up of alternating layers LiAl2(OH)6 and Al2O4(OH)2Si8O12 having several polytypes. Cookeite is often found as a product of hydrothermal alteration of silicates in pegmatites. It forms at relatively low temperatures (below 200 °C) and variable pressures.
Chrysanthemum stone.
Drilling rig.
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