different between feldspar vs peralkaline

English

Partial calque of German Feldspat, formed from Feld (“field”) + Spat (“spar”).

feldspar (countable and uncountable, plural feldspars)

(mineralogy) Any of a large group of rock-forming minerals that, together, make up about 60% of the earth's outer crust. The feldspars are all aluminum silicates of the alkali metals sodium, potassium, calcium and barium. Feldspars are the principal constituents of igneous and plutonic rocks.

per- +? alkaline

peralkaline (comparative more peralkaline, superlative most peralkaline)

(geology) Describing igneous rocks that have a higher ratio of sodium and potassium to aluminium than is needed to produce feldspar

Send