Mineral Specimen #1274 Pumpellyite-Mg, Copper, Calcite with included Copper, Quartz and Microcline in Amygdule Basalt
Keweenaw Couny, Michigan, USA
Type Location
Ca2MgAl2(Si2O7)(SiO4)(OH)2·H2O
This is a very complex specimen of amygdule basalt from Michigan's Copper District. Much of the outer surface is coated with micro crystals of dark green Pumpellyite-Mg (which are quite nice under magnification). Mixed in with the Pumpellyite are small Copper crystals. Some of these are enclosed in clear Calcite crystals. Below this upper layer is a layer of clear to white Calcite with much included Copper. Below this layer, is a layer of milky Quartz with a thin layer of reddish Microcline. Below this is the basalt filled with amygdules filled with a variety of minerals. Some of these are filled with Pumpellyite crystals with Copper crystals. Others are filled with Calcite and others are filled with Quartz crystals. There are some other amygdules with a coating of fibrous, pinkish orange material which is likely Laumonite. The specimen is in fairly good condition with the exception that some of the Calcite crystals on the outer surface are damaged.
9.4 x 8.7 x 4.7 cm
Sold Specimen retained as part of the Minerals Sold But Not Forgotten Galleries
