This gem is most prized when its color is pigeon's blood red
[DOC] [TLE] The Problem with Pigeon's Blood | Gem Obsessed [PAR] May 25, 2016 ... Prices for these so-called 'pigeon's-blood red' rubies ranged from ... GIA is also 
as liberal in its use of the designation, restricting mention of it to a ... the most 
expensive colored gemstone to sell at auction in the United States.