Gemstones
Aquamarine Buying Guide: Natural vs Lab-Grown, Prices per Carat & Quality
Santa Maria blue, eye-clean clarity, heat treatment, large carat sizes and aquamarine prices.
What is aquamarine?
Aquamarine is blue to greenish-blue beryl coloured by iron. Hardness: 7.5–8 on the Mohs scale.
Colour and quality factors
Intense pure blue (the 'Santa Maria' trade style) commands the highest prices; pale stones are affordable. Expect eye-clean clarity.
Origins and natural (mined) stones
Brazil, Nigeria, Mozambique, Madagascar and Pakistan.
Carat weight and size
Large crystals are common, so 5–20 ct stones are attainable; colour intensity matters more than size.
Prices per carat
Pale: roughly $50–$200/ct. Medium blue: roughly $200–$600/ct. Fine intense blue: roughly $600–$1,500+/ct. These are indicative retail ranges per carat gathered from published trade and auction reporting; real prices vary widely with colour, size, origin and treatment, and are not a Riakoob quote.
Natural vs lab-grown (synthetic)
Synthetic aquamarine is rarely marketed; simulants include blue spinel, glass and blue topaz. Under US FTC guidelines a lab-made stone must be clearly described as laboratory-grown, laboratory-created or synthetic, never simply by the gem name.
Treatments you must know about
Most aquamarine is heated to remove green and is stable. Treatment disclosure is required; ask for it in writing and on the lab report.
Certification
For significant aquamarine purchases, ask for a report from an independent lab such as GIA, AGL, SSEF or Gübelin stating natural or synthetic origin, any treatments and, where relevant, geographic origin.
Care and durability
Good for rings; clean with warm soapy water.
Buyer checklist
- ✓ Eye-clean
- ✓ Pure blue rather than greenish (preference)
- ✓ Not blue topaz sold as aquamarine
Verification tools & references
Every Riakoob piece arrives certified, insured and covered by our 12-month value promise.
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