Aragonite in sputnik form, exhibiting the excellent twinned crystal habit in which the crystals radiate outwards, similar in appearance to the famous Russian satellite 'Sputnik', hence the nickname. The crystals are a bright orange colour and when viewed from certain angles, the orthorhombic shape of the crystals can be seen. Aragonite is one of the two naturally occurring crystaliine forms of calcium carbonate, the other being calcite. It is formed by biological and physical processes, including precipitation of water from marine and freshwater environments. These aragonite "sputniks" were collected from Morocco, available only as 1.5"x 1.5" or 3" x 2" size mineral specimens they will come supplied in a labelled card tray.