\Cal"cite\ (k[a^]l"s[imac]t), n. [L. calx, calcis,
lime.] (Min.)
Calcium carbonate, or carbonate of lime. It is rhombohedral
in its crystallization, and thus distinguished from
aragonite. It includes common limestone, chalk, and marble.
Called also {calc-spar} and {calcareous spar}.
Note: Argentine is a pearly lamellar variety; aphrite is
      foliated or chalklike; dogtooth spar, a form in acute
      rhombohedral or scalenohedral crystals; calc-sinter and
      calc-tufa are lose or porous varieties formed in
      caverns or wet grounds from calcareous deposits; agaric
      mineral is a soft, white friable variety of similar
      origin; stalaclite and stalagmite are varieties formed
      from the drillings in caverns. Iceland spar is a
      transparent variety, exhibiting the strong double
      refraction of the species, and hence is called doubly
      refracting spar.