I am well into the next tranche of minerals for the Illustrated Minerals of Australia. Next month’s Monthly Mineral Chronicles will include the minerals görgeyite to grossite.
One of the ones in between is the cadmium sulphide, greenockite.
Greenockite occasionally occurs as red or orange crystals that sometimes fluoresce an intense red colour. But it is more commonly found as a yellow coating either on or near sphalerite from where it has sourced its cadmium. Sometimes, this is greenockite, or hawleyite, or a mixture of the two.
One of the specimens that I have photographed for the next issue has this yellow coating on sphalerite from the Kara Mine in Tasmania. However, it wasn’t until I had finished the stacking process that I realised there are also tiny orange crystals of greenockite present. Have a look at the high resolution version on Mindat and Zoom in, particularly in the bottom left quadrant, and you will spot them. Neat!
Below: Sphalerite, Greenockite, Kara Mine, Hampshire, Tasmania. Width of view 7.75mm. Click on the image for a higher resolution version.
Greenockite. I'm envious. Several times I was close, but they were duds. Someday.....