@moriartysgemart: Do you think nature can produce straight lines like this!? It seems almost unfathomable that these cubes have not been machined, cut, or polished… Believe it or not, they are natural pyrite crystals that formed within the earth! They’re found about 3 hours northeast of Madrid in Spain. The pyrite crystals from this mine have a beautiful metallic luster, sharp cubic angles, and can be found inter-grown in clusters or as single cubic structures! Super cool! If you think these are neat, you should check out all the unique crystals and mineral specimens (including all of these pyrite specimens) on our website: MineralMike.com #amazing #earth #nature #unbelieveable #crystals #mineralspecimens #geology #beautiful #cube #metallic #collectable #pyrite #noway #rocks