Chromitite
“Layers of pure chromium ore”
Chromitite is a dark, heavy igneous rock composed almost entirely of the mineral chromite, making it the world's only significant source of chromium. It forms as dense cumulate layers within large mafic-ultramafic intrusions where chromite crystals settled out of cooling magma.
chromite (90%+), olivine, orthopyroxene, plagioclase (minor), platinum group minerals
Bushveld Complex (South Africa), Great Dyke (Zimbabwe), Kemi (Finland), Orissa (India), Oman Ophiolite
5.5-6
The Bushveld Complex in South Africa contains over 70% of the world's known chromite reserves — a single geological structure holding the key to global stainless steel production.
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