Psilomelane (Manganese)
Psilomelane is found as a secondary mineral in the oxidized zone of manganese deposits. Its Associated Minerals are Pyrolusite and manganite. It gets its name from the Greek "psilo" for smooth and "melane" for black. Psilomelane, also known as black hematite, is a group name for hard black manganese oxides such as hollandite and romanechite. Psilomelane consists of hydrous manganese oxide with variable amounts of barium and potassium. Black hematite is an interesting unfounded name given because botryoidal Psilomelane roughly resembles hematite ("kidney ore") Psilomelane but has a black streak (color of its powder) whereas hematite has a red streak.
Psilomelane has gem uses similar to those for hematite and with the same limitations, which relate to its relatively high specific gravity. "Drusy Psilomelane," in particular, has been used for wire-wrapped pendants, silver accented Brooches and spheres.
Item # PSIL03120051
15 oz Lot of Silver Crown Psilomelane Rough
Listed here is a rough lot of Crown of Silver Psilomelane, from Chihuahua, Mexico. This classic old wide-band material is sometimes referred to as 'black malachite'. They are not in the same groups and there's no real affiliation. It features a well defined pattern of bands and a strong fortification like banding in shiny smoky chrome alternating with satin black. There are several pieces that have been marked for lapidary cabochons. This material came from an old lapidary acquaintance years ago. The weight is 15.2 oz (just under 1 lb)