Genuine Iron Pyrite Cubes, Completely naturally forming. Cubic formations are common in the crystal world, although the best examples are Iron Pyrite. These from naturally in pockets in the earth and can be plucked as you see here. Do not expect all side to be perfect, or a perfect cube. These items are "Cubic", not perfect cubes, however you should expect specimens like the ones shown here. Sizes can vary, this batch are circa 1cm wide. Origin - Spain.