Assertion: orthoclase | /r/CapableOf | contain of potash
Facets:
value: from 15
type: TEMPORAL
Source sentences:
text: Orthoclase and microcline contain from 10 to 15 per cent, of potash, and for that reason rocks rich in potash feldspar, notably those of the syenite type, are sometimes used in a crushed condition as fertilizers.