Page:A treatise on diamonds and precious stones including their history Natural and commercial.djvu/165

 SECT IX.

On the Turquois.

color of the Turquois is beautiful celestial blue, which migrates into pale blue, and is sometimes tinged with green. It is destitute of that lustre which distinguishes most of the precious stones; it is also opaque, and does not admit of a very high polish; there is, therefore, nothing but its very agreeable hue which can recommend it to the notice of the jeweller. The latter character it possesses in no inconsiderable degree, and retains it unimpaired by candle-light. It has always been fashionable; and although great quantities have been imported, so as to render small stones extremely cheap, yet it has continued to be in considerable demand.