lutecite

lutecite

[′lüd·ə‚sīt]
(geology)
A fibrous, chalcedony-like quartz with optical anomalies that have led to its being considered a distinct species.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
(2011) lutecite. From detritic sand deposit, north of Le grand Pressigny, France.
Lutecite: pseudofibrous, length-slow, oblique extinction.
Most spherules are composed of chalcedony; some consist of megaquartz or quartzine and lutecite (Fig.
Apparently only the mineralogy has changed; quartzine and lutecite have replaced the anhydrite.