October 2, 2019Day 38 Scroll down to content Day 38 of the 365 to 40 project. I have no idea what this mineral is in my rock collection but I love the cubic crystal structure on the surface. Some of these cubes are just a few millimetres across. Share this: Share on Reddit (Opens in new window) Reddit Share on X (Opens in new window) X Share on Facebook (Opens in new window) Facebook Share on Pinterest (Opens in new window) Pinterest Published by dawnstarau View all posts by dawnstarau