Linked from
The 18 pages that link to Plagioclase, each with the reason it gives.
BasaltRelated: Plagioclase is commonly a major mineral in basalt.
AndesiteRelated: Plagioclase is typically andesite’s main mineral constituent.
GabbroRelated: Plagioclase is typically gabbro’s dominant light-colored mineral.
AmphiboliteRelated: Plagioclase is the other principal mineral group in typical amphibolite.
TonaliteRelated: Plagioclase is one of tonalite’s dominant minerals.
DaciteRelated: Plagioclase is typically the dominant mineral in dacite.