noun
dogtooth spar
A mineralogy term referring to a variety of calcite with scalenohedral crystals resembling canine teeth.
犬牙石は方解石の一種で、犬の牙のような結晶をしている。
Dogtooth spar is a variety of calcite that forms crystals resembling canine teeth.
From 犬 (dog) + 牙 (fang) + 石 (stone), describing the fang-like crystal shape.