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Magma-Source Controls on Initial Sn–W Enrichment in Granites: A Review

  • Hua-Wen Cao

Received: 25 Mar 2026 | Revised: 20 May 2026 | Accepted: 08 Jun 2026 | Published: 10 Jun 2026

Highlights

  • Systematically reviews controls on initial Sn–W enrichment during partial melting.
  • Identifies key controversies in source composition, pre-enrichment, and melting conditions.
  • Proposes the integration of in situ analysis and modeling to study disequilibrium melting.

Abstract

Tin and tungsten are strategic critical metals, and understanding the mechanisms responsible for their extraordinary enrichment is a frontier research topic in economic geology. The formation of granite-hosted Sn–W deposits involves three successive stages: source enrichment, magmatic transport, and metal precipitation. Partial melting of metasedimentary rocks in the middle–lower crust represents the starting point for the initial enrichment of ore-forming metals, yet the role of this stage in mineralization has long been insufficiently recognized. This review focuses on the controls exerted by magma-source processes on the initial enrichment of Sn and W during granite petrogenesis. It systematically summarizes research progress concerning source-rock composition, the degree of pre-enrichment of ore-forming elements, anatectic conditions, including temperature and oxygen fugacity, the types of minerals involved in melting reactions, and the stability of accessory minerals. Key scientific controversies remain, including the respective contributions of metapelites versus metagreywackes to mineralization, the mechanisms controlling Sn–W coupling and decoupling, and the fractionation behavior of elements and isotopes during disequilibrium melting. Future research should integrate in situ microanalysis, phase-equilibrium modeling, and isotopic tracing, using recently exhumed orogens such as the Himalaya as natural laboratories, to elucidate the mechanisms of Sn–W mobilization and initial enrichment during partial melting and thereby advance theories of granite-related Sn–W metallogeny.

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DOI
10.63335/j.hp.2026.0043
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Volume 2, Issue 2
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Cao, H.-W. (2026). Magma-Source Controls on Initial Sn–W Enrichment in Granites: A Review. Habitable Planet, 2(2), 355–364. https://doi.org/10.63335/j.hp.2026.0043
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