Although fine ruby can occur in any corundum mine, rubies from Myanmar (formerly Burma) are famous for their top-color traffic-light-red hues. Since these rubies form with little iron in them to suppress their fluorescence, they appear to glow.
For Burmese rubies, be sure to have a reputable laboratory confirm their origin.
In sizes under two carats, unenhanced stones from Myanmar can command prices two to three times that of a heat-treated stone from other sources. Larger unenhanced rubies can command much higher prices, up to ten times more than heat-treated rubies of similar size.
Heat-treated material from Myanmar commands a more modest price bump of about 25% above material from other sources.
Except for a few rare cases, rubies from other locales don’t command a premium in today’s market. However, rubies from novel sources like Montana can sell for somewhat higher prices due to their rarity.
Appraising Color in Rubies
Aside from premium origins, color is the most important factor when appraising rubies. Unlike diamonds, color in rubies is…