Assertion: obsidian | /r/ObjectUse | used in scalpel
Facets:
value: currently
type: TEMPORAL
Source sentences:
text: Obsidian is famous for producing an edge thinner and sharper than the best surgical steel, and is currently being used in scalpels for some of the most precise surgery.
text: It has also been known to be used in knives and scalpels, because of its sharpness and the ability for the substance to become thinner than even a surgical steel scalpel.