Assertion: osmium's vapor pressure | /r/HasProperty | difficult to machine
Facets:
value: because of its hardness
type: CAUSE
value: because of brittleness
type: CAUSE
Source sentences:
text: Because of its hardness, brittleness, low vapor pressure (the lowest of the platinum-group metals), and very high melting point (the fourth highest of all elements, after only carbon, tungsten, and rhenium), solid osmium is difficult to machine, form or work.