A classic from a very old American locality that is a varietal of enstatite but apparently still a valid species as I read it. Note the curving, bronzy," well-defined crystals. From the noted W.W. Jefferis (1820-1906) Collection. According to MINDAT, this was a "copper mine located about 1 mile NW of Mt Washington and about 3 miles NW of Baltimore. Started 1845 and closed 1880. Reopened during the period 1905." Jefferis handling of the specimen would have been from the heyday of the mine, in the mid 1800s. Note the early musuem accession number 6846, as well. This is a big, somewhat showy, display-worthy specimen from a long-vanished locality, proably under a building for 100 years now.