Page:A treatise on diamonds and precious stones including their history Natural and commercial.djvu/157

 sard or sardoine is considered to be a beautiful variety of chalcedony, and,when perfect, of one uniform tone of color, which is yellowish brown, or reddish brown, of lighter or darker tints, sometimes approaching black; it is more or less translucent when held between the eye and a strong light. When it exhibits angular lines of lighter colors, it is called Oriental Agate. It is generally found in the alluvial soil, and has often been met with in searching for gold and diamonds. It also oceurs stalactitic and forming geodes.

ancients selected this substance, and the following variety, to engrave upon, no doubt from its possessing two peculiar and necessary qualities, namely hardness and tenacity, by which it is capable of receiving the