Laforêtite mineral

Laforêtite is the silver-indium sulfide mineral species AgInS2, listed as approved by IMA-CNMNC in September 2026 under 1995-006. Meisser and colleagues' original description concerns tiny natural inclusions in a single galena specimen collected from the Montgros mine dumps in Haute-Loire, France. Reflected-light observations, eight electron-microprobe analyses on two grains, and in-situ X-ray diffraction support the mineral assignment. The diffraction measurement used a roughly 20 by 30 micrometre inclusion; galena reflections were removed, and preferred orientation limits comparison of intensities with the separate synthetic reference. The natural material was assigned to the tetragonal low-temperature AgInS2 form. The authors' laboratory synthesis produced a multiphase comparator, not a pure natural specimen or microbial product; synthetic hardness measurements and preparation temperatures are not natural-specimen measurements. This species is distinct from elemental indium, bulk mine waste, and manufactured AgInS2 polymorphs considered solely by chemical formula. The sampled inclusions establish neither a bulk resource grade nor an extraction yield. No microbial mechanism, industrial recovery claim, or constituent-derived criticality designation is assigned.

Record source: data/records/laforetite.yaml