Psilomelane is actually manganese oxide. Silver Tree, or Psilomelane
in Quartz and Silver Crown Psilomelane are manganese oxide in cryptocrystalline
quartz. It is a very hard agate material that is easy to cut and polish.
However, Psilomelane tends to gum up saw blades. So make sure your
blades are well dressed before and after slicing.
Psilomelane in Quartz (Silver Tree Psilomelane) came from the Golden
Crown Mine, which was close to the long closed Silver Crown Mine.
The Golden Crown Mine produced a tiny small amount of golden and red
agate with whisps of psilomelane, as well as Psilomelane in Quartz
(Silver Tree Psilomelane). Sadly, both mines were closed years ago
and this material has become more difficult to obtain.
Psilomelane cuts like any other agate and takes a high polish with
tin oxide, cerium oxide or diamond. It cuts very attractive gems.
Mohs hardness 7.
Example of Psilomelane in Quartz (Silver Tree Psilomelane) Cabochon