Carnelian Octagonal Handcut. Carnelian is the  reddish-brown variety of the Chalcedony crystal family, closely aligned to Agates. As with Agate, the interior structure of Chalcedony is not properly crystalline, but Chalcedony is considered finer than ordinary Agate and has an interior chemical structure more crystalline than Agate.
Chalcedony is more rare than Agate, comes in a number of colours, and has from ancient times always been appreciated. The reddish-brown Carnelian has probably been most loved but Black Onyx is also well-known, and the lavender colour in Chalcedony has been much used in jewellery in the 20th.century, particularly in Northern Europe and North America.