Members of the phyllosilicate group are:

• A. Calcite, dolomite, aragonite
• B. Kaolinite, muscovite, chlorite
• C. Halite, gypsum, anhydrite
• D. Quartz, feldspar, olivine

Answer: (B)

Phyllosilicates are sheet silicates that form layered structures built from silicate tetrahedral sheets stacked with octahedral sheets, giving a characteristic platy or micaceous habit and perfect sheet cleavage. The minerals kaolinite, muscovite, and chlorite are classic examples of this group: kaolinite is a 1:1 phyllosilicate with one tetrahedral sheet per octahedral sheet, muscovite is a 2:1 phyllosilicate with two tetrahedral sheets sandwiching an octahedral sheet, and chlorite is also a 2:1 phyllosilicate that includes an extra brucite-like layer between the sheets, which influences its appearance and cleavage.

The other mineral sets do not belong to the phyllosilicate group: calcite, dolomite, and aragonite are carbonates; halite, gypsum, and anhydrite are halides and sulfates, respectively; quartz, feldspar, and olivine are not sheet silicates but framework or single/chain silicates.