Phosphourus occurs in nature in the ferm of stable phosphate. (Animal bones also contain calucium p-hosphate (58%) The important minerals are
(i) Phosphorite, $$ Ca_{2}(PO_{4})_{2} $$ (ii) Chloraptite, $$ Ca_{3}(PO_{4})_{2} CaCl_{2} $$ ,
(iii)Fluoraptite, $$ Ca_{3}(PO_{4})_{2} CaF_{2} $$
These are some deposits of nitrates and phosphates in earth's crust. Nitrates are more soluble in water. Nitrates are difficult to reduce under the laboratory conditions but microbes do ti easily compounds of phosporus and nitrogen are used as fertilizer.
Amongs the following which is not member of apatite family
A
$$ Ca_{9}(PO_{4})_{6}.CaF_{2} $$
B
$$ Ca_{9}(PO_{4})_{6}.CaCl_{2} $$
C
$$ Ca_{9}(PO_{4})_{2}.Ca(OH)_{2} $$
Correct option is D. None of these