Thayer's Greek Lexicon

 1. jasper, a precious stone of various colours (for some are
purple, others blue, others green, and others the colour of brass)

++++
There is one kind called the Aeizusa, like to air and another
Crystallizusa, clear as crystal. So Pliny speaks of a white Jasper
called Astrios, and which, he says is "crystallo propinquans", near
to crystal, found in India, and on the shores of Pallene. (Gill)