Gems Notes and Extracts Augusto Castellani, Mrs. John Brogden 1871

HAUYNA. 125very rare, and the few that are to be met with belongmost certainly to the Greco-Komano school.Likenesses of the Persian kings belonging to theSassanidee dynasty may be often seen engraved onthese gems.Nothing is more easy than to recognise an antiqueintaglio on garnet; because, being very brittle, thegreater number of them found are broken or in fragments.Besides, time confers on them a softness ofcolour which defies imitation byeven the ablest artists.XLVILHAUYNA.FROM the illustrious Abbe Haiiy, one of the mosteminent mineralogists, this stone takes the namewhich, in compliment to him, was givenitby Monti -celli.It was first discovered by Gisniondi, who, having metit associated with mica and green pirosene, on MountsLaziali, called it, hence, Lazialue.Afterwards, Monticelli found it on Vesuvius.The hauyna, then, is a substance composed of alumina,silex, potash, protoxide of iron, sulphuric acid andsoda, and of which, according to the celebrated LuigiCeselli, the exact analysis is as follows :