Sell your diamond to people who truly understand it
We buy diamonds, fine gemstones and valuable jewellery directly from private sellers. Free valuations, with no auctions or intermediaries. Established in Milan in 2009.
What we buy
Choose the item you would like to sell to go straight to our free, no-obligation valuation form.
How it works
Request a valuation
Complete the form or message us on WhatsApp, attaching photographs and grading reports if available.
Professional valuation
A gemmologist reviews your enquiry and arranges an appointment if needed.
Our direct offer
La Diamanteria makes its own offer, with no auctions or intermediaries.
Payment
If you accept our offer, we pay by bank transfer.
We make our own offer
ComproDiamanti.it is La Diamanteria's direct buying service. We do not auction your diamond or offer it to a network of buyers. If it meets our requirements, we make you an offer ourselves.
One point of contact for a straightforward process.
We buy directly
The offer comes from us, with no intermediary involved.
Five generations of diamantaires
A documented family history in the diamond trade.
Gemmological assessment
We examine the stone's characteristics and any available documentation.
Based in Milan
Appointments at Via Vincenzo Monti 47, with payment by bank transfer.
Our showroom at Via Vincenzo Monti 47, Milan
ComproDiamanti.it is run by La Diamanteria at Via Vincenzo Monti 47 in Milan. A physical showroom, direct contact with the buyer and a professional valuation.
Our main requirements
We assess natural diamonds of one carat or more per stone, with a GIA, HRD or IGI report, or without a report. We do not buy laboratory-grown diamonds or diamonds with AIG, GRA, GWLAB or ALGT reports. We buy selected watch brands and also assess rubies, sapphires and emeralds weighing less than two carats.
View all criteria →Read what our clients say
Reviews are published directly on our Google profile. If you have used our service, your feedback can help others choose a trusted diamond buyer.
Frequently asked questions
For an immediate valuation, message us on WhatsApp or call +39 02 466891.
Contact a specialist diamond buyer. La Diamanteria has been buying directly from private sellers in Milan since 2009. We assess each stone using gemmological criteria and, if it meets our requirements, make our own offer, with no auctions or intermediaries.
We assess natural diamonds of one carat or more per stone, with a GIA, HRD or IGI report, or without a report. We do not buy synthetic diamonds or diamonds with AIG, GRA, GWLAB or ALGT reports. We also assess rubies, sapphires and emeralds under two carats.
For an immediate valuation, message us on WhatsApp or call +39 02 466891. Alternatively, complete our online enquiry form. A gemmologist will review your request; the final valuation is made after examining the stone at our showroom.
A diamond's price depends on the 4Cs: carat weight, colour, clarity and cut. Fluorescence, proportions and an internationally recognised grading report also matter. We refer to current market prices in Antwerp, Tel Aviv, New York, Dubai and Mumbai.
Guides and insights
All guides ↗A free valuation. An offer directly from us.
Complete the form or message us on WhatsApp, attaching photographs and grading reports if available. A gemmologist will review your enquiry.