THE MINERAL PAPAGOITE

Chemistry: CaCuAlSi₂O₆(OH)₃; Calcium Copper Aluminum Silicate Hydroxide
Class: Silicates
Subclass: Cyclosilicates
Uses: Only as a mineral specimen
Specimens

Papagoite is another rare copper silicate from the mines of Arizona, USA. It is found at only one mine in Arizona, the New Cornelia Mine, Ajo District in Pima County. The only other world-wide location is at Messina, Transvaal, South Africa. The Arizona mine is the type locality. Papagoite is one of only a few four membered ring silicates. These silicates have four silicate tetrahedrons linked into a ring forming a distorted square-like structural element. Papagoite is named for the Papago Indian tribe of Arizona. It forms as a secondary mineral on slip surfaces and in veins in altered granodiorites.

PHYSICAL CHARACTERISTICS:

Color is a dark sky blue in crystals and a paler blue in massive veins.
Luster is vitreous to dull.
Transparency: crystals are translucent.
Crystal System is monoclinic; 2/m.
Crystal Habits include tiny flattened, elongated crystals sometimes formed into spherical aggregates and massive vein filling material.
Cleavage is imperfect in one direction.
Hardness is 5 - 5.5
Specific Gravity is approximately 3.3 (slightly above average for non-metallic minerals)
Streak is pale blue.
Associated Minerals are limited to aurichalcite, ajoite, barite, shattuckite and limonite.
Notable Occurrences include the New Cornelia Mine, Ajo District in Pima County, Arizona, USA and Messina, Transvaal, South Africa.
Best Field Indicators are crystal habit, associations, color and locality.