【化】 冰洲石
【医】 冰岛晶石[矿](晶形碳酸钙)

[ noun ]
a transparent calcite found in Iceland and used in polarizing microscopes
<noun.substance>

Iceland spar \Ice"land spar`\ (Min.)
A transparent variety of calcite, the best of which is
obtained in Iceland. It is used for the prisms of the
polariscope, because of its strong double refraction. Cf.
{Calcite}.