Silver

A thick, exposed vein of silver naturally adhered to the host rock. Some silver leaf can be seen on the specimen. As well, some post mining arsenide mineralization or "cabinet growth". This specimen comes from the Silver Princess Mine, which was brought into production in 1907 and shut down sometime in the mid 1920's. From 1908 to 1922 the mine produced 3,713.806 oz. of Ag. The deposit was mined from a shaft 230ft deep with four levels.*

*https://www.mindat.org/loc-19097.html