Chalcopyrite epitaxial on sphalerite

Mineral Matters #215

This week’s Facebook Mineral of the Week Group’s selected theme is epitaxy! This term was explained in Mineral Matters #212 a couple of days ago.

This one is a classic and really cute example of epitaxy. Chalcopyrite crystals have grown epitaxially on a face and edges of a sphalerite crystal.

And to add to the cuteness, there are some tiny tetrahedrite crystals bottom left of photo! I didn’t notice these until after I had taken the photo!

Below: Chalcopyrite, Sphalerite, Tetrahedrite, Hellyer Mine, Hellyer-Que River Mines, Waratah district, Waratah-Wynyard municipality, Tasmania. Width of view 6mm.

Click on the image for a higher resolution version.