Identify the incorrect pair from the following :
Fluoroapatite $-3 \mathrm{Ca}_3\left(\mathrm{PO}_4\right)_2 \cdot \mathrm{CaF}_2$
Carnallite $-\mathrm{KCl} \cdot \mathrm{MgCl}_2 \cdot 6 \mathrm{H}_2 \mathrm{O}$
Cryolite $-\mathrm{Na}_3 \mathrm{AlF}_6$
Fluorspar $-\mathrm{BF}_3$
