Iron pyrite, FeS2, is made up of the elements iron and sulfur. Its crystal structure is cubic; however, there are very few places in the world where near-perfect pyrite cubes form naturally underground with sharp edges and shining, mirror-finish sides. One of those rare locations is Navajun, a tiny village nestled in the Alcarama Mountains in northeastern Spain, known for producing the world’s most beautiful pyrite cubes.
These cubes in matrix are from the Navajun mine, meticulously extracted from the earth, still embedded in the host rock. The host rock is marl, a sedimentary rock consisting of clay and lime.
Besides being cleaned, it has not been altered in any way. Their shape and sheen are completely natural.
Do not soak these specimens in water, or the marl will soften and disintegrate.
