Which mineral is the main ore of chromium?

Chromite is the main ore of chromium.

Chromite is an iron chromium oxide with the approximate formula FeCr₂O₄. It is usually black or dark brown, has a submetallic luster, and belongs to the spinel group. The mineral is dense and commonly occurs as grains disseminated through ultramafic and mafic igneous rocks.

Chromium is valued for its resistance to corrosion and ability to produce hard, shiny alloys. Most chromium is used in stainless steel and other alloy steels, while chromium compounds have applications in pigments, chemicals, and plating.

Chromite deposits often form when dense minerals separate from cooling magma or accumulate in layered igneous intrusions. It is distinct from crocoite, a bright red lead chromate mineral that contains chromium but is not the principal commercial chromium ore.