The House · Diamantaires OG
How to Know if Your Diamond Is Really Worth Something?
That's the question many people ask themselves before contacting us. And it's the right question to ask — because an unnecessary trip wastes everyone's time. Here are the 5 essential criteria to assess whether your diamond really has market value.
1. Is the diamond natural?
This is the number one eliminator. A lab-grown diamond (CVD or HPHT) is worth 80 to 95% less than a natural diamond of the same appearance. If your ring was purchased after 2018 at a reduced price, chances are it is a synthetic diamond. Only a trained gemologist can determine this with certainty.
2. Is there a GIA or IGI certificate?
A GIA certificate (Gemological Institute of America) or IGI is your diamond's passport. It guarantees the stone is natural and documents its precise characteristics: weight, color, clarity, cut. A certified diamond sells for 15 to 30% more than an uncertified diamond with the same characteristics. Without a certificate, our gemologists can still analyze your stone on-site.
3. Carat weight
Below 0.3 carats, the market value of a single diamond is generally limited. Value increases exponentially with weight:
| Weight | Standard quality | High quality |
|---|---|---|
| 0.5 carat | €1,500 – €2,500 | €3,000 – €5,000 |
| 1 carat | €4,000 – €7,000 | €8,000 – €18,000 |
| 2 carats | €12,000 – €22,000 | €25,000 – €60,000 |
4. Is the jewelry signed by a major house?
A Cartier ring, a Van Cleef & Arpels bracelet, or a Boucheron necklace have additional value tied to the house's signature. These pieces resell significantly better than unsigned jewelry, even with equal stone quality. The presence of the original box and certificate of authenticity further increases value.
5. Color and clarity
A D-F (colorless) diamond or VVS-IF clarity is worth much more than a yellowish diamond or one with visible inclusions. If you see inclusions with the naked eye, market value will be limited. Conversely, a visually clean diamond with a nice white color can be worth several thousand euros even without a certificate.
What we do not buy
- Lab-grown diamonds (synthetic) — resale value nearly zero
- Gold-plated or gilt metal jewelry with no intrinsic value
- Fancy stones (zirconia, crystal, rhinestone)
- Antique jewelry without real stones or house signature
Unsure? Have your diamond appraised for free
Our GIA-certified gemologists analyze your stone in minutes and give you an honest answer. The appraisal is free, with no obligation, and entirely confidential.
43 Rue Beaubourg, 75003 Paris — walk-ins or by appointment
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✉ [email protected]
Our services
Free and without obligation appraisal
Combien valent vos bijoux ?
In-person appraisal by a state-certified gemologist — firm offer, immediate payment, with complete confidentiality.