The Collaborative International Dictionary of English v.0.48:

Balas ruby \Bal"as ru`by\ [OE. bales, balais, F. balais, LL.
   balascus, fr. Ar. balakhsh, so called from Badakhshan,
   Balashan, or Balaxiam, a place in the neighborhood of
   Samarkand, where this ruby is found.] (Min.)
   A variety of spinel ruby, of a pale rose red, or inclining to
   orange. See Spinel.
   [1913 Webster]

WordNet (r) 3.0 (2006):

balas ruby
    n 1: a pale rose-colored variety of the ruby spinel [syn:
         balas, balas ruby]