Andradite

specimen number:
2102202

location:
Garnet Hill, Calaveras Co., California, USA

description:
Choice grouping of lustrous sharply formed andradite crystals. This is in good condition. Classic locality for the species.

Garnet Hill, located near Moore Creek in Calaveras County, California, is a classic American locality renowned for its well-formed andradite garnet specimens. Geologically, the site represents a contact metamorphic skarn where Mesozoic granitic rocks of the Sierra Nevada Batholith intruded into Paleozoic metasedimentary rocks, specifically the Calaveras Complex limestones. This intense heat and chemical exchange resulted in the formation of large, sharp, dodecahedral andradite crystals, which typically range in color from olive green to dark brownish-black and are often found in association with epidote, quartz, and idocrase. Historically, the site has been known to mineralogists since the late 19th century and has been a popular destination for collectors for over a hundred years. While not a commercial industrial mine, the hill saw peak activity from mineral specimen prospectors during the mid-20th century. Today, it remains a significant site for field collectors and educators, serving as a textbook example of contact metasomatism within the Mother Lode region of the Sierra Nevada foothills.

Questions about this specimen?
Send an email or call us: 314-341-1811.