Fluorite with Geocronite Pyrite and Sphalerite

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The discovery, in 2024, of an unusual occurrence of green Fluorite crystals sat upon bright sparkling golden Pyrite crystals really brought Peruvian minerals back to the attention of the mineral collecting world. Due to the remoteness of many of the mines in the Andes mountains several names were used, but it is now accepted that these wonderful specimens came from Milpo mine in the Atacocha mining district. This superb display specimen is one of the better larger crystallized specimens we have seen from this find, with a striking display of the contrast between really well-formed cubo-octahedral Fluorite crystals and their bright golden metallic Pyrite host. Forming a ridge of crystals, the Fluorite covers roughly one side of this linear specimen, with many perfectly shaped geometric crystals, the largest reaching 3 cm across but many others to 2.5 cm. Internally, they are transparent and glassy, with a vibrant green, perhaps best described as a paler emerald-green, and this colour is most obvious on one side of the crystals facing upwards, with a white internal frosting seen on the other side of the crystals typically associated with minor sulphide crystals perched upon the surface. This colour-zoning adds an interesting and unusual dynamic to this super display piece, but does impact the overall lustre seen on the Fluorite crystal faces. The sulphide crystals sparsely scattered upon the surface of the Fluorite crystals include Sphalerite, Pyrite and Geocronite, the latter as tiny gun-metal grey hexagonal pyramids. Underneath the Fluorite the rib of dense sulphide matrix is dominated by bright pyritohedron-cubic Pyrite crystals but with internal pockets containing Galena, Sphalerite, Arsenopyrite and Geocronite. There is some minor bruising to some of the Fluorite crystals, but this is really not that obvious from a display perspective and the overall surface of intergrown cubo-octahedral Fluorite crystals presents the crystallography of this wonderful Fluorite extremely well. A really fine larger Peruvian Fluorite.