A. coal
B. gypsum
C. iron pyrites
D. chlorapatite
✅ The correct answer is option D.
Sulphur is not present in chlorapatite. Chlorapatite is formed in fluor-deficient environments, and found in calcium silicate marbles, in layered mafic intrusions and in diabases. It is known to replace triphylite in some granite pegmatites (Ptáček 2016). A monoclinic polymorph, chlorapatite-M is known.
Sulphur is not present in chlorapatite. Chlorapatite is formed in fluor-deficient environments, and found in calcium silicate marbles, in layered mafic intrusions and in diabases. It is known to replace triphylite in some granite pegmatites (Ptáček 2016). A monoclinic polymorph, chlorapatite-M is known.