Search Mineralpedia – A Mineral Photo Database and Identification Guide

Named to honor Abbe Christophe Gaudefroy, a French mineralogist who worked in Morocco where the mineral gets its type locality at the Tachgagalt mine. Additional localities for Gaudefroyite include at the N’Chwaning I, II, and III mines and the Wessels and Black Rock mines in the Northern Cape Province of South Africa. It occurs as an uncommon hydrothermal mineral in manganese deposits.

Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/gaudefroyite.pdf

Named after Dr. Thomas Geiger of Switzerland who stidies the Falotta manganese ores where Geigerite gets its type locality in the Falotta mine in Switzerland. It occurs in two additional localities in the Gozaisho mine on Honshu Island in Japan and at the Monte Negro mine in Liguria, Italy. Geigerite is found formed by the metamorphism of manganese oxide ores in radiolarite cavities.

 Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/geigerite.pdf

Named after the Latin word gemini, meaning “twins,” as the mineral is often extensively twinned. Localities for Geminite include in France, the Czech Republic, Germany, as well as newer localities in Morocco, and Namibia. This rare mineral occurs in oxidized arsenic-bearing lead-copper deposits at its type locality at Cap Garonne in France, and from mine dumps at a gold-bearing arsenic sulfide deposit at Salisigne, also in France.

Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/geminite.pdf