This siderite specimen is from the Julcani Mine in the Julcani District, Angaraes Province, Huancavelica Department Peru. This mine contains dozens of different minerals including siderite. It is a carbonate containing the elements Fe C and O. This attractive piece consists of thin quartz crystal matrix that is topped with druse siderite and a pair of rhombic interpenetrating twin crystals. They have dark green cores with lighter golden exteriors and a chatoyant appearance. This piece measures 1 3/8 x 1 3/8 x 1 inches or 35 x 35 x 25 mm.