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Glite Dictionary
🪨 Light rock 🪨 Light igneous
felsic

felsic

9.3
Light-colored igneous rock or mineral high in silica and feldspar
  • adjective
  • /ˈfɛlsɪk/
  • Specialized
: felsico
  • Granite is a common example of a felsic rock, characterized by its light color and high silica content.

Examples

  • The last element of the primary igneous microstructure to be lost during textural equilibration is the grain shape, as can occur during the high-grade metamorphism of felsic igneous rocks.

    Academic text (2018)

  • If this second, now apparently ruling, paradigm were correct, felsic plutonic rocks should be somewhat more mafic than their supposed complementary volcanic fractions, but this is not supported by the statistical evidence.

    Academic text (2018)

  • Many felsic minerals are essential for the formation of light-colored granite and rhyolite.

  • I learned that felsic igneous rocks typically contain a high percentage of feldspar and quartz.

Synonyms

rhyolitic
vsfelsic
  • Specialized
1 9.5

Made from a light-colored volcanic rock that has a lot of silica

is a general term for light igneous rocks rich in silica and feldspar
silicic
vsfelsic
  • Specialized
1 8.1

Containing a lot of silica, like some rocks and volcanic magma

includes silica but also emphasizes light color and feldspar content
feldspathic
vsfelsic
  • Specialized
1 9.4

Containing the mineral feldspar that is common in many rocks and ceramics

includes silica and light color as defining traits not only feldspar

Antonyms

mafic
  • Specialized
1 8.6

A dark rock or mineral like basalt that is rich in iron and magnesium

How Siliceous

siliceous
  • Specialized
1 9.9
felsic
  • Specialized
9.3
intermediate
45 3.6
mafic
  • Specialized
1 8.6

Surface Forms

felsic positive

Morphology

felsic = feldspar + silica (semi-transparent) = fels + ic

The combining form 'fels-' encodes the idea of feldspar/silica and the adjective-forming '-ic' is regular, but 'fels-' is not a standalone English word and the term is technical.

Etymology

Felsic comes from combining feldspar and silica, the two light minerals it contains, so felsic describes rocks that are rich in these minerals and therefore 'light' in color.