Size  8cm x 4cm
 
One of the old style pyrolusites from the original Iron baron pit. Druzy pyrolusite crystals coating voids in massive matrix. The pyrolusite is much more shiny silver colour than the photos show, pyrolusite is very hard to photograph. 
Collected around the late 70's early 80's by Glyn Francis. This pit was closed  not long after and has not been re opened in recent times.  The matrix possibly has silica in it as other specimans from here have chalcedony balls on them as well, and it is unusually hard to break/trim or cut. The back has been cut on a saw because of the hard matrix.