Merensky Reef

geological feature, South Africa

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June 30, 2026

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The Merensky Reef is a significant geological feature located in the Bushveld Complex of South Africa. This complex, intruded approximately 2.1 billion years ago, is the world's largest repository of magmatic ore deposits. The Merensky Reef is particularly noted for its rich deposits of platinum-group metals, producing a major fraction of the world's supply. It is composed of stratiform layers of various rock types, including dunite and norite, and formed through a process called magmatic concentration, where immiscible sulfide liquids segregated from a cooling magma. This process scavenged and concentrated elements like copper, nickel, and platinum-group metals, leading to the formation of valuable ore deposits.12

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mineral deposit
Immiscible melts
…in this way are the Merensky Reef of the Bushveld Complex, producer of a major fraction of the world’s platinum-group metals; the Stillwater Complex, Montana, host to platinum-group deposits similar to the Merensky Reef; and the Norilsk deposits of Russia, containing large reserves of platinum-group metals.
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…in this way are the Merensky Reef of the Bushveld Complex, producer of a major fraction of the world’s platinum-group metals; the Stillwater Complex, Montana, host to platinum-group deposits similar to the Merensky Reef; and the Norilsk deposits of Russia, containing large reserves of platinum-group metals.
Read More