Source : Webster's Revised Unabridged Dictionary (1913)

Cacholong \Cach"o*long\, 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'']
   (Min.)
   An opaque or milk-white chalcedony, a variety of quartz;
   also, a similar variety of opal.