Noun

(mineralogy) A hard, reddish brown chalcedony; used in jewelery,

* 1952' ''You were in Eden, the garden of God; every precious stone was your covering, '''carnelian , topaz, and jasper, chrysolite, beryl, and onyx, sapphire, carbuncle, and emerald; and wrought in gold were your settings and your engravings. On the day that you were created they were prepared. — Ezekiel 28:13 RSV.

Noun

(en noun)

A transparent purple variety of quartz, used as a gemstone.

* {{quote-magazine, date=2012-03

, author=Lee A. Groat , title=Gemstones , volume=100, issue=2, page=128 , magazine=(American Scientist) citation , passage=Although there are dozens of different types of gems, among the best known and most important are […] . (Common gem materials not addressed in this article include amber, amethyst , chalcedony, garnet, lazurite, malachite, opals, peridot, rhodonite, spinel, tourmaline, turquoise and zircon.)}}

(uncountable) A purple colour.

(tincture) The purple tincture when emblazoning the arms of the English nobility.