Notes on anglesite, anthophyllite, calcite, datolite, sillimanite, stilpnomelane, tetrahedrite and triplite

Earl V. Shannon
1920 Proceedings of the United States National Museum  
Basin, Gunnison County, Colorado. The specimen consists of a mass of ocherous and cellular limonite, upon and in the cavities of which the anglesite crystals are scattered. These crystals, which reach an extreme diameter of about 7 millimeters, are all identical mbination but VF ig. 1.-Crystal of anglesite. in CO differ slightly in form, / \ o "'t he larger individuals being tabular parallel to d{102), while the smaller and more perfect crystals are prismatic by elongation parallel to the b
more » ... rallel to the b axis, the appearance being as illustrated in figure 1. The forms identified on these crystals are as follows: Pinacoids, c (001). 5(010). Prisms, 7^1(110), x(130). Domes, o (Oil), t?(021), <^( 102)! Pyramid, s(132). The faces of the prism x{lS()) and the pyramid s(132) are completely rounded and etched. The remaining faces are brilliant and yield excellent reflections of the signal, although the dome d{102) is commonly striated parallel to the elongation. ANGLESITE CRYSTALS FROM THE TINTIC DISTRICT, UTAH. The anglesites from the Tintic district are now rather widely distributed and are consequently well known. They have been described by Farrington,^Rogers,and Hiilyak.^The extreme variability of anglesite in form and habit makes it profitable to examine the 1 FaiTington and Tillotson, Fjeld Col. Mus.
doi:10.5479/si.00963801.58-2345.437 fatcat:g4xptuj3fvgcjiq4a3fnzohjsy