Source : Webster's Revised Unabridged Dictionary (1913)

Chalkstone \Chalk"stone`\, n.
   1. A mass of chalk.

            As chalkstones . . . beaten in sunder. --Isa. xxvii.
                                                  9.

   2. (Med.) A chalklike concretion, consisting mainly of urate
      of sodium, found in and about the small joints, in the
      external ear, and in other situations, in those affected
      with gout; a tophus.

Source : WordNet®

chalkstone
     n : a deposit of urates around a joint or in the external ear;
         diagnostic of advanced or chronic gout [syn: {tophus}]