aventurine, tavanturine

[Fr. from Ital. avventura = chance, with reference to the accidental discovery of No. 1.] 1. A brownish gla with gold-coloured spangles, first made at Murano, near Venice. The chance dropping of bra -filings into a pot of melted gla led to the discovery. 2. A brownish-pink colour. 3. Min.: Quartz, spangled with scales of mica or some other mineral. The best specimens have been found in Spain. aventurine felspar. 1. A variety of Orthoclase. 2. A variety of Albite or Oligoclase.