Word Study
cacholong
CIDE DICTIONARY
cacholong, n. [F. cacholong, said to be from Cach, the name of a river in Bucharia + cholon, a Calmuck word for stone; or fr. a Calmuck word meaning “beautiful stone”].
An opaque or milk-white chalcedony, a variety of quartz; also, a similar variety of opal. [1913 Webster]
OXFORD DICTIONARY
cacholong, n. a kind of opal.
Etymology
F f. Mongolian kashchilon beautiful stone
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