Assertion: boron | /r/CapableOf | form refractory materials
Facets:
Source sentences:
text: Industrially, very pure boron is produced with difficulty, as boron tends to form refractory materials containing small amounts of carbon or other elements.
text: Industrially, very pure boron can be produced, but this is difficult, because boron tends to form refractory materials that contain small amounts of carbon or other elements.