Assertion: pure boron | /r/HasProperty | produced with difficulty
Facets:
value: industrially
type: OTHER
Source sentences:
text: Industrially, very pure boron is produced with difficulty because of refractory contamination by carbon or other elements.
text: Industrially, very pure boron is produced with difficulty because of refractory contamination by carbon or other elements.
text: Industrially, very pure boron is produced with difficulty, as boron tends to form refractory materials containing small amounts of carbon or other elements.