Wolframite

Wolframite is the primary ore of tungsten, the metal with the highest melting point of any element (3,422°C). It forms in high-temperature hydrothermal veins associated with granitic intrusions, often alongside cassiterite (tin ore), quartz, and arsenopyrite.

The mineral is actually a solid solution series between two end members: ferberite (iron-dominant, FeWO₄) and hübnerite (manganese-dominant, MnWO₄). Most specimens contain both iron and manganese and are simply called wolframite.

The name has a colorful etymology. Medieval German tin miners noticed that certain dark, heavy minerals contaminated their tin smelting, causing the tin to foam and reducing yields. They called it 'wolfram' (wolf's froth or wolf's cream) because it 'ate the tin like a wolf.' The element tungsten takes its symbol (W) from this name. 'Tungsten' itself comes from Swedish: 'tung sten' meaning 'heavy stone.'

Wolframite is identified by its dark brown-black color, submetallic luster, bladed to tabular crystal habit, very high specific gravity (7.0-7.5, remarkably heavy for a non-metallic-looking mineral), and one perfect cleavage direction.

Distinguish from tourmaline (lighter SG, different luster), columbite-tantalite (similar appearance but even heavier), and ilmenite (different streak, trigonal). The extreme heaviness is the most immediate diagnostic clue: wolframite feels much heavier than it looks.