| Dark green to black Actinolite crystals with hairlike Byssolite. Keystone is a classic Alpine Cleft formation if you are in the Alps. It is a rock Quarry now not used and the quarry is filled with water as a deep pond. When active, some pocket in its walls yield Byssolite, Adularia, Fluorapatite (rare), Quartz, Calcite, Actinolite, Prehnite specimens which have not been able to be collected for many years and are very limited on the mineral market. I was able to get specimens from a Pennsylvanian collection about 10 years ago after another collector highgraded it. I bought the bulk since he only wanted a few specimens to enhance his collection of Pennsylvania minerals. Needless to say no apatites left. The few are now in his collection. |
