Judging quality
Look for glowing red rather than brownish or purplish tones. Nearly all commercial ruby is heat-treated; lead-glass-filled ruby is much lower value and must be disclosed.
Corundum
Ruby
Red corundum, colored by chromium, and the hardest gem material after diamond. Ruby in zoisite and ruby in fuchsite are the common specimen forms; gem crystals from Mogok are the historic ideal.
Care
Extremely hard and safe to clean, though glass-filled stones must avoid heat and acid.
History & lore
The Mogok Stone Tract in Burma has produced ruby continuously for over five centuries, its finest color known as 'pigeon's blood'.
Cultural history, recorded as tradition rather than as medical or scientific claim.
Common questions about Ruby
- What is Ruby?
- Red corundum, colored by chromium, and the hardest gem material after diamond. Ruby in zoisite and ruby in fuchsite are the common specimen forms; gem crystals from Mogok are the historic ideal.
- How hard is Ruby and what is it made of?
- Ruby is a Corundum-family mineral with the composition Al2O3. It crystallizes in the trigonal system and rates 9 on the Mohs hardness scale. It occurs in red, pink-red.
- Where does Ruby come from?
- Notable localities for Ruby include Myanmar (Mogok), Mozambique, Madagascar, Tanzania.
- How do you tell good Ruby from filler?
- Look for glowing red rather than brownish or purplish tones. Nearly all commercial ruby is heat-treated; lead-glass-filled ruby is much lower value and must be disclosed.
- How do you care for Ruby?
- Extremely hard and safe to clean, though glass-filled stones must avoid heat and acid.
See it in person
Photographs only go so far
Both rooms are open six days a week, and there is always someone happy to pull pieces out of the case so you can compare them under the light.