from The American Heritage® Dictionary of the English Language, 4th Edition
- n. See plagioclase.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A plagioclase feldspar, the second member of the Albite-Anorthite solid solution series. Primarily found as small crystals in impure marble. Oligoclase contains a small amount of calcium substituting for some of the sodium in its formula. Oligoclase with reddish-golden inclusions found in Norway and Canada is called sunstone.
from the GNU version of the Collaborative International Dictionary of English
- n. A triclinic soda-lime feldspar. See feldspar.
from The Century Dictionary and Cyclopedia
- n. A soda-lime triclinic feldspar, the soda predominating. See feldspar.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. any of a series of triclinic feldspars that form rocks
oligo- + Greek klasis, cleavage (from klān, to break; see plagioclase).(American Heritage® Dictionary of the English Language, Fourth Edition)
From oligo- + clase (Wiktionary)