Its specific gravity is equal to 2-603.
When
looked at against the light it is transparent, and appears more yellow
than red; otherwise, its colour is more that of dark marone.
Nevertheless, it is found of varied tints, from blackish-red to light
ohesnut.
The beauty of the sard as used for engraving consists in the purity and evenness of colour, when looked at through the light.
When a sard is very hard, it takes the name of Oriental sard, in accordance with the term applied to the most precious stones.
This agate is brought from India, Arabia, Egypt and Armenia.
Bohemia
and Silesia also yield us sards, but they are much inferior. Engravers
despise them on account of their smoke-coloured tint, sprinkled with
bluish spots.
In substance the sard appears to resemble the plasma very much, excepting in the colour.
Scipio
Africanus is the first of whom it is related that he continually wore a
sard ring on his finger : this is told us by Dimostrato.
The
origin of its name is disputed. Pliny believes it to be that this stone
was originally found near Sardis, chief city of Lydia. He says,
however, that very beautiful sards are found on the mountains of
Maranai, near Babylon, and on the confines of Egypt.
Others think that this name is derived from Sardinia; but Cesio and St. Epiphanius maintain that it is
