Assertion: granite's quartz | /r/HasProperty | sio
Facets:
Source sentences:
text: Fractional crystallisation serves to reduce a melt in iron, magnesium, titanium, calcium and sodium, and enrich the melt in potassium and silicon - alkali feldspar (rich in potassium) and quartz (SiO 2 ), are two of the defining constituents of granite.