Pyrite crystal cubes in metamorphosed shale form the famous Great Open Cast at Parys Mountain, Isle of Anglsey, Wales. Tbhe cubic crystals are very small, seen much easier with aid of a magnifier but they are brassy colouredand have good crystal habit. The crystals are set within a heaviliy metamorphosed shale, so altered, that no longer resembles shale in the slightest, even being the opposite colour. Parys mountain its self was once the largest copper mine in Europe during the 18th century. Initially, small scall extraction began durin ght eearly Bronze age some 4000 years ago. During the 18th Century, extensive mining began to occur until the shafts eventually collapsed in on them selves, thus creating a large open pit which is known as the 'Great Open Cast'. Today, the area remains barren and desolate, with only few specialist plants and bacteria remaining which can survive the harsh chemical conditions left over by the old mine works. So otherworldly the site looks that it has been used for sequences featured in British sci-fi drama Doctor Who and the 1997 martial arts film based on the video game, Mortal Kombat. These specimens are rare and collected many years ago, available in a range of sizes they will come supplied in a card tray with an information label.