Concept:
Fluorspar is the mineral form of calcium fluoride. It is commonly used as a flux in metallurgical and ceramic processes.
Step 1: Fluorspar is another name for the mineral fluorite.
Step 2: Fluorite is chemically calcium fluoride.
Step 3: Calcium forms:
\[
Ca^{2+}
\]
Fluoride ion is:
\[
F^-
\]
Step 4: To balance the charge, one calcium ion combines with two fluoride ions:
\[
Ca^{2+}+2F^- \rightarrow CaF_2
\]
Therefore, the formula of fluorspar is:
\[
\boxed{CaF_2}
\]