Rhodochrosite cabochons oval shapes perfect with silver jewelry layout. These 2 pieces weight is 105.75 cts and the dimension of bigger is 21×39×7 MM. The Mineral rhodochrosite. Rhodochrosite is a very aesthetic and desirable mineral; its deep red and hot pink crystals are highly sought after. ... They formed from precipitating water dripping from the manganese-rich rock inside the ancient mine tunnels, and kept on growing over the centuries into large stalagmites. Rhodochrosite is a manganese carbonate mineral with chemical composition MnCO₃. In its pure form, it is typically a rose-red color, but impure specimens can be shades of pink .