Phrenite was named after Colonel Von Prehn who brought the first specimen to Europe from the Cape of Good Hope where he discovered it. It is found in various shades of green, yellow and brown. Its hardness of 6.0-6.5 makes it very suitable to be used in jewelry. The present cabochon, highly suitable for mounting in a ring, possesses excellent luster and a beautiful green color with an inner glow.
Weighing approximately 21.3 carats and measuring 19.0 x 15.0 x 10.0mm