Datolite with Copper

Unknown Owner

A cut and polished one half of a datolite nodule, the attractive interior color due to native copper. I think a really neat an interesting historical specimen. This comes with an antique label and was originally sold by American dealer Lazard Cahn in 1912. The Quincy Mine in Houghton County, Michigan was one of the most important mines in the Keweenaw Peninsula copper district. Mining began in 1846 and focused on native copper found in basalt and conglomerate rock formations. The operation became known as the "Old Reliable" because it paid dividends for many years during the 19th and early 20th centuries. Underground workings produced large amounts of native copper before the mine closed in the mid 20th century. Lazard Cahn was an American mineral dealer and collector active during the late 19th and early 20th centuries. He lived in Colorado Springs, Colorado and handled mineral specimens from many important mining districts in the United States. Cahn supplied specimens to collectors, museums, and universities and issued printed labels with many of the minerals he sold. Specimens with his labels are still found in older collections and are valued for their historical provenance.