Question

Froth flotation method cannot be employed for the concentration of:

• A. Zinc blende
• B. Pyrolusite
• C. Copper pyrites
• D. Cinnabar

Answer 1

The correct option is B Pyrolusite

Pyrolusite $\left(Mn{O}_2\right)$ is an oxide ore, while zinc blende $\left(ZnS\right)$, copper pyrites $\left(CuFe{S}_2\right)$ and cinnabar $\left(HgS\right)$ are sulphide ores. Only sulphide ores are purified by froth flotatlon.

Hence, froth flotation method cannot be employed for the concentration of pyrolusite.

Option B is correct.