Dims: 2.4" x 1.9" x 1.9" (6.1 x 4.8 x 4.8 cm)
Wt: 5.11 oz. (145.1 g)
Gold Hill Mine, Tooele County, Utah, U.S.A.
This specimen consists of a very thin coating of Conichalcite on a layer of halloysite, a kaolinitic mineral. The Conichalcite layer has a bright color that is a bit too yellow to be considered grass-green. It shows no crystal form and has no luster. I almost get the feeling that someone made a mixture of green and yellow food coloring, and dripped it onto areas of the halloysite. The halloysite itself is also amorphous and has a dull luster, though there is a very small spot that seems to be nearly polished, but I don't think intentionally so. It is soft enough to scratch with a fingernail, and it has a very pale blue coloration. The host rock has a rusty coloration and seems to be botryoidal in nature. I think that it is made up of goethite, though it reminds me a bit of bauxite. There are a few very small areas, however, that have a dark gray-black coloration and a shiny, almost metallic luster. Under 10-power magnification, they appear to be either hematite or cuprite, I cannot tell which (probably hematite). I like pieces like this, because there is the element of the unknown involved with them, and I think it is fun to try to figure out such little "mysteries".