Fluorite displays in a more broad range of colors than any other mineral, although remarkably the purest form is colourless. This mint green specimen has a slight powdered snow texture, with an cubic structure. The colors come from "colour centers", which are pattern impurities on the atomic level. Fluorite also glows when exposed to UV light, and is where we get the word "fluorescence" from. It can also emit light in the dark (phosphorescence), when heated (thermoluminescence), as well as when crushed or rubbed (triboluminescence). Traces of uranium and other rare earth impurities are thought to be the cause of this glow. Crystals are usually cubic, although they can also be octahedral or botryoidal.
11x14in/28x35.5cm professional archival print, on 300 gsm 100% cotton fine art paper. Print date and artist initials on back. Optional artist handmade oak frame is about 12x15in/30.5x38cm, mounted with archival mat and backboard.