Assertion: asterism | /r/HasProperty | rare
Facets:
value: extremely
type: DEGREE
Source sentences:
text: Familiarity information: ASTERISM used as a noun is rare.
text: The Asterism is a rare typographic mark used similarly to ellipses (⁂), a group of stars, a star pattern found in a gemstone, and a Nashvillian design studio.
text: Asterism is an extremely rare natural phenomenon; it is an optical effect in the shape of a star found on Cabochon stones like rubies and sapphires.
text: The reason that asterism is so rare is that it requires the gem to have inclusions of rutile needles, and for the needles to be aligned in such a way as to reflect light in a multi-rayed pattern forming a star.