Where to sell a diamond in Paris, and to whom? Solitaire, antique diamond, loose stone, on its own or in a lot, with or without a certificate: each stone is examined in front of you, then bought at its fair value.
A diamond is valued according to the 4Cs — carat, colour, clarity, cut — and the state of the market. We examine your stone, mounted or not, certified or loose, singly or in bulk, and make an immediate offer to buy it. The house is a diamond dealer in Paris (in French): it buys diamonds for its own stock and sells them on to its clients, in France and abroad. Before entrusting your stone to a public auction, compare the two routes: selling at auction or to a dealer (in French).
Complimentary appraisal, immediate offer and immediate payment. Here is what we look for first and foremost.
Solitaires, wedding bands and rings set with diamonds.
Rose cut, cushion, old European and period cuts — how to recognise them (in French).
LFG, HRD, IGI — mounted or loose.
Fancy, yellow, brown and rare stones.
High-value diamonds, examined in depth.
Loose diamonds, lots and stock.
It makes the valuation easier and more secure, but it is not required: we examine your stone on the premises.
Yes, mounted or loose, singly or in lots.
Bring it in by appointment, with its certificate if it has one, or send us photographs: a first opinion within 24 hours.
Yes. Once agreement is reached, payment is made the same day, by bank transfer or by cheque, whatever the amount — with no fees or commission.
Yes. The absence of a certificate does not change the nature of the stone: we examine it on the premises, by eye and with the dealer's instruments, and make a firm offer. An existing certificate makes the valuation easier; it is never a condition.
To a diamond dealer who buys directly and can make you a firm offer. On rue Drouot, Maison Altmann examines your diamond in front of you, with or without a certificate (LFG, HRD, IGI…), tells you what it is worth on the market, and then you decide. Compare if you wish: we encourage you to do so.
Yes. These stones are shown by appointment, in complete discretion; the diamond does not leave your sight, the offer is firm and payment follows agreement, the same day, whatever the amount.
Yes: a fine old cut, a sought-after shape (pear, heart, cushion, emerald), a particular colour — all of these count. We look at the stone, not just its paperwork.
Yes. Whether it is mounted in a piece of antique jewellery or has simply been worn, only the stone counts — weight, colour, clarity, cut. Wear to the mounting plays no part in the valuation of the diamond.
Verifiable facts, reviewed in September 2026. For a specific case, the appointment settles the matter.
The four Cs — carat, colour, clarity, cut — read against the current week's Rapaport, then fluorescence, actual cut quality and the certificate, if there is one.
A period or signed solitaire is sold mounted. Never unset a stone before the opinion: the mounting can be worth more than the diamond alone.
Above €5,000, a flat-rate tax of 6.5% (or, on request, the capital-gains regime), declared by the professional buyer. Firm offer on the spot, immediate payment.
We tell you what you own, then what we offer you for it: a firm offer, settled the same day. The choice remains yours.
Book an appointment+33 7 81 11 49 2922 rue Drouot, 75009 Paris