Gemstones
Gemstone Treatments You Must Know
Heating, oiling, irradiation, fracture filling and coating — what's acceptable and what destroys value.
Common and accepted
Heating of sapphire and ruby, oiling of emerald and irradiation of blue topaz are widespread and stable.
Value-reducing
Glass filling, surface coating, diffusion and dyeing must be disclosed and dramatically lower value.
The law
Under the FTC Jewelry Guides and EU consumer law, sellers must disclose treatments that significantly affect value.
Verification tools & references
Every Riakoob piece arrives certified, insured and covered by our 12-month value promise.
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