Search Mineralpedia – A Mineral Photo Database and Identification Guide
Named for John Johnston O’Neill, as a geologist with the Geological Survey of Canada and Professor of Geology and Dean of Science and Dean of Engineering at McGill University in Montreal, Canada. The type and only locality for Oneillite is at the Poudrette quarry at Mont Saint-Hilaire in Quebec, Canada where it is found at a contact between a vein of albite and the nepheline syenite. Oneillite occurs as yellow to brown anhedral grains.
Ref. Minerals and their Localities, Bernard, J.H. and Hyršl, J. (2004)
IMA/CNMNC List of Mineral Names (2009) and Canadian Mineralogist 37 (1999), 1295
More appropriately spelled Ordoñezite, Ordonezite is named after Ezequiel Ordoñez, a Mexican geologist and former Director of the Geological Institute of Mexico. Ordonezite is a rare mineral that is deposited at its type locality at the Santin mine in Mexico as a late stage mineral with pneumatolytic tin ore within fractures through rhyolite. Other newer localities for Ordonezite include Canada, Germany, the USA, and possibly Switzerland.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/ordonezite.pdf
Named for the Latin word auripigmentum, meaning “golden paint,” in reference to Orpiment’s golden-yellow color. Orpiment is somewhat common in small amounts, however excellent crystal specimens are rare and can be found in localities in the United States, Slovakia, Bosnia-Herzegovina, Macedonia, Iran, Turkey, Russia, Georgia, China, and Peru. It occurs “in low-temperature hydrothermal veins, hot springs, and fumaroles,” and is also commonly found as a product of the alteration of arsenic minerals, in particular, realgar.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/orpiment.pdf
Named as an orthorhombic (ortho) mineral and its relationship to pinakiolite. Orthopinakiolite is a rare mineral found only at its type locality at Långban in Sweden where it occurs “in veinlets in granular dolomite in a metamorphosed Fe-Mn orebody.” Orthopinakiolite occurs in association with hausmannite, manganophyllite, dolomite, and calcite.
Ref. Handbook of Mineralogy, Anthony et al (1995) and MSA at http://www.handbookofmineralogy.org/pdfs/orthopinakiolite.pdf