Sardonyx (Hastings' Dictionary)

The name indicates the structure of the gem, a layer of sard and one of onyx. Pliny (NN 37, 86) says : Sardonyches olim . . intellige- bantur candore in sarda, hoc est veluti came ungui hominis imposita et utroque tralucido. The finest then cauie from Arabia and India. In the latter country it was found in torrent-beds, some pieces being larpe enough for sword handles.

It is better adapted lor cameos than for signets, but was much used by the Romans for both purposes, and it possesses one quality valuable for a seal : wax does not adhere to it. Juvenal twice refers to sardonyx seals — • Ar^it ipsorura quog littera eremmaque princeps Sardonycbum, locuiis qua custoUitur ebumis' (SoL xlU. USX ' Ideo conducta Paullus agebat Sardonyche , . ' (i6. vii 14-1).

This gem has always been easy to produce artifici- ally, either by joining together layers of different stones or by placing a sard on a red-hot iron, when the ■surface exposed to the heat becomes of an opaque white colour. The sardonjx (aapSivvi) is the fifth foundation- stone of the New Jerusalem (Rev SI*"). RVni gives sardonyx as an alternative for diamond in trans- lating ciSn; at Ex '28" 39", but at Ezk 28" RV con- tents itself with the diamond of the text.

There is no sulKcient reason for supposing that D'iSn; means sardonyx. The Ox/. Heb. Lex. is inclined to deri re oiSn; from D^n, and to explain the name as pointing to the hardness of the stone. This would not favour the identification with the sardonyx. J. Taylor. and