Seylan Gems & Jewelry
Most gems in the world trade are treated in some way. The failure is not the treatment. The failure is a listing that hides it. We want the treatment line to be readable without a trade dictionary.
Specifications
Typical published ranges used in gemology. Specific gravity below matches our carat calculator default where applicable. (SG 4.00)
| Heat | Common for sapphire and ruby; can improve color or clarity |
|---|---|
| Unheated | No heat treatment, stated for that stone, and usually worth a premium when the color is already fine |
| Oil or resin | Traditional clarity treatment for emerald; the filler should be named when known |
| Irradiation | Used for some blue topaz and other colors; the color may be stable, and the listing should still say so |
| Filling | Glass or resin in fractures; more serious than routine heat, and it changes care and value |
| None stated | Ask. Absence of a word is a question, not a free upgrade |
Heating sapphire or ruby in a controlled way is an old and accepted practice. It does not make the stone “fake.” It does change the price relative to an unheated stone of similar looks. If we say heated, price it as heated. If we say unheated, that claim is doing real work and should not be a decorative adjective.
Unheated does not mean untreated in every other sense, and it does not mean inclusion-free. A natural unheated sapphire can still show silk, crystals, and a window if the cut is poor.
Emeralds are routinely oiled or filled because the species is included. A traditional oil is not the same disclosure as a hardened resin, and a laboratory report is the clean way to say which. Care follows the filler: heat, solvents, and ultrasonic cleaning can alter it. We would rather tell you that before you clean the ring in a machine.
Do not compare an oiled emerald’s price per carat with an unheated sapphire’s. They are different markets.
The treatment we know belongs in the listing in ordinary language. If we do not know, we should not invent “unheated” to make the stone easier to sell. You can ask us to walk through the wording on a specific item. Bring the questions to a consult if the stone is important enough that a laboratory document should exist before you pay.
This page does not certify any stone. The product page and any report that belongs to that stone are the record.
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Sapphire
Ruby
Alexandrite
Emerald
Padparadscha
Aquamarine
Spinel
Garnet
Peridot
Tourmaline
Tanzanite
Citrine
Quartz
Chrysoberyl
Apatite
Topaz
Amethyst
Lolite
Zircon
Sinhalite
Cats Eye
Opal