indium-geology-and-deposits

Indium is a chalcophile trace element with a low crustal abundance of approximately 56 ppb Verified Answer #1. There are no primary mines in the world where indium is the principal economic commodity Verified Answer #1. Due to its chemical similarity to zinc, indium is concentrated almost exclusively within base-metal sulfides, primarily sphalerite Verified Answer #1. Zinc-indium deposits are polymetallic systems that often contain tin, copper, silver, lead, and tungsten Verified Answer #1. These deposits are formed through magmatic-hydrothermal processes that enrich indium within zinc ores Verified Answer #1.

Recovery and Reserves

Indium is recovered strictly as a byproduct during the smelting and refining of zinc Verified Answer #1. Approximately 95% of the global supply of refined indium is linked to the processing of zinc concentrates Verified Answer #1. Only an estimated 15% to 20% of mined indium is successfully recovered into high-purity refined metal due to high losses throughout the mineral processing and smelting value chain Verified Answer #1. This structural and metallurgical dependency introduces significant uncertainty regarding global reserve calculations Verified Answer #1.

Global Examples

Significant indium enrichment is defined as a bulk ore grade exceeding 30 g/t Verified Answer #1. The Dulong Sn-Zn-In deposit in Yunnan Province, China, is a major global example of such enrichment Verified Answer #1.

Dulong Sn-Zn-In Deposit