Phosgenite

An old time specimen of beautifully crystallised Phosgenite (lead chlorocarbonate) from its type locality at Bage mine, Cromford, Derbyshire, England.  When first discovered the species was known as ‘Cromfordite’ for the first few years.  This thumbnail specimen has a 10 x 8 x 6 mm, almost perfect tetragonal Phosgenite crystal attached to a small matrix of massive Galena and probable Baryte.  The crystal is translucent light grey with a dark grey, almost black film coating its top face and two ends, while the long side prism faces remain uncoated.  Due to its age, probably collected around 1850, there are two slight scratch marks on the crystal’s upper prism face.  Two old labels are glued beneath the matrix, one numbered ‘17’ and the other, its original price of $2.  Those were the days!  This charming specimen comes in an original square, rather worn, black box with intact glass lid and a Harvard University Mineralogical Museum collection label, numbered 84477.