Mimetite w/ Bayldonite (old classic) Kay Robertson Coll.

Item Description

Excellent old-time mimetite on bayldonite from the Upper Oxidized Zone at Tsumeb. Classic, lustrous, translucent, straw-yellow, hexagonal prisms are richly and aesthetically clustered atop the crust of green bayldonite, a rare hydroxyl Pb-Cu arsenate. The crystals have interesting creamy coating of secondary mimetite, adding character. The impressive, stout, large mimetite is 2.2 cm. A classic, old-time, colorful and very showy two-sided combination from the Kay Robertson Collection # 6999 and acquired from the Lidstrom's at the 1973 San Francisco Show. Kay's label is incorrect. These are definitely mimetites, not pyromorphite crystals. Kay is a prominent California collector, who specialized in European classics (see the article in the March-April, 2007 Mineralogical Record).