Sri lankan "Geuda". 97pcs mix sapphire

This lot consist of 97 pcs of geuda rough which has to be heated to get the desired colour tone.
Heating Geuda sapphires dates back to 600A.D. According to field-gemmology sri lankans used blown pipes at the beginning. Now a days Geuda treatment is done using traditional lakmini furnace and other technologically advanced electric and gas furnace.

Few falls in to young geuda. Origin sri lanka.