A mineral deposit is a naturally occurring concentration of minerals in the Earth's crust. ORE, VEIN, LODE, and placer are all types of mineral deposits. ORE is a mineral deposit that can be mined for profit. VEIN is a narrow, sheet-like body of mineral ORE that is often found in rock formations. LODE is a mineral deposit that is found in veins or fissures in rock. Placer is a mineral deposit that is formed by the action of water, usually in a stream bed.