Double-terminated alstonite crystal group on a sulphide matrix (sphalerite, pyrite and galena). Also present but not in photo are twinned harmotome crystals. The sphalerite is providing the orange colour in the alstonite crystals. Width of...
It’s interesting to see a specimen with a paragenesis. In this instance, a double-terminated is surrounded by drill-bit twinned harmotome, but also has a harmotome perched on the alstonite crystal. The alstonite also has a...
Double-terminated alstonite crystal on a tiny bit of sulphide matrix. Width of view 3.5mm. Stack of 50 images. Click on the image below for a higher resolution version…
Double-terminated alstonite crystal on a tiny bit of sulphide matrix (sphalerite and galena). Width of view 3.5mm. Stack of 40 images. Click on the image below for a higher resolution version…
Tom Cottrell 2/2005
Tom Cottrell 2/2005
A neat pseudomorph of barite after alstonite from Nentsberry Haggs Mine, Nent Valley, Alston Moor District, Cumbria, England. Photo width 20mm.
