And how do untreated gemstones compare to treated gemstones? Van Dell explains. At the Salt Lake City ROADSHOW In August 2016, jewelry expert Katherine Van Dell appraised this ca. 1900 emerald ...

Counterintuitively, these beautiful untreated sapphires in a kaleidoscope of colours pay the miners less than the stones that end up being treated do. Fernando Jorge, a Brazilian jeweller based in ...

CHANTHABURI, Thailand -- In late 2001, this bustling market town near the Thai-Cambodian border was suddenly, and inexplicably, flooded with padparadschas -- rare orange-pink sapphires whose name ...