- Metamorphic rock commonly formed by
and composed of quartz. No
rock cleavage. Breaks through
grains in contrast to sandstone, which breaks around grains.
Source: Leet, L. Don. 1982.
Physical Geology, 6th Edition. Englewood Cliffs, NJ: Prentice-Hall
- a. A granoblastic metamorphic rock consisting mainly of quartz and formed
by recrystallization of sandstone or chert by either regional or thermal
metamorphism; metaquartzite. CF: orthoquartzite
b. A very hard but unmetamorphosed sandstone, consisting chiefly of quartz
grains that are so completely cemented with secondary silica that the rock
breaks across or through the grains rather than around them; an
c. Stone composed of silica grains so firmly cemented by silica that
fracture occurs through the grains rather than around them.
d. As used in a general sense by drillers, a very hard, dense sandstone.
e. A granulose metamorphic rock consisting essentially of quartz.
f. Sandstone cemented by silica that has grown in optical continuity
around each fragment. Syn: ganister
Dictionary of Mining, Mineral, and Related Terms