Noun

(uncountable, mineral) A mineral of pegmatite deposits, often 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 diamond, ruby and sapphire, emerald and other gem forms of the mineral beryl , chrysoberyl, tanzanite, tsavorite, topaz and jade.}}

(countable) An example (a stone) of the mineral beryl.

The crown was set with six beryls of excellent size and color.

(uncountable) A dull blueish green colour.

Noun

(en noun)

(mineral) A calcium fluoride phosphate of variable composition, sometimes used in the manufacture of fertilizer.

* 1967', Duncan McConnell ''et al.'', "Infrared Absorption of Carbonate '''Apatite ," ''Science, New Series , vol. 155, no. 3762, p. 608,

We had prepared, by precipitation methods, finely divided crystalline apatites' that were similar in crystal size and x-ray diffraction profile to bone ' apatite .