Mammoth Mine (Mammoth shaft), Tintic District, East Tintic Mts, Juab Co., Utah, USA
Miniature, 4.5 x 3.2 x 2.6 cm
Erinite is one of the most confusing old-time mineral synonyms. It was used as a synonym for chalcophyllite and cornwallite (related copper arsenates) and for a green variety of spessartine. A well-placed vug in sulfide matrix is richly lined with elongated, acicular, emerald-green microcrytals. Chalcophyllite and cornwallite can both be emerald-green and both are found at the Mammoth Mine of the Tintic District in Utah. Chalcophyllite is generally a platy mineral, so we believe this specimen is cornwallite. A bit of azurite is a nice accent. The collection this came out of was a museum stash dating to prior to World War I.