Note 19 — On Scarabs.ToC
Reading edition
This is chalcedony penetrated by minute green fibres of hornblende. It is now found principally in India and China. The color is frequently equal to that of the finest emerald, but the yellow patches or black spots running through it, distinguish its species. Ancient specimens have been found free of these marks and very transparent. They may have had a method in ancient times of freeing the stone from these spots.