77 Diamonds

2nd Floor, 3 Hanover Square, W1S 1HD · View on Google Maps · Visit website · 02035401477

Founded in 2005 by Vadim Weinig, a third-generation diamond merchant, and Tobias Kormind, who came from investment. The Mayfair showroom opened in 2013. The model is straightforward: you filter an enormous inventory of certificated loose stones down to a shortlist, then pair your chosen diamond with a setting.

The number is the whole argument. Around 1.8 million certificated stones is an inventory no Hatton Garden independent can approach, and it changes what is possible. If you want a specific combination of carat, colour, clarity and cut, you can very likely find it rather than being talked toward what is in the safe.

The trade-off is that this is a curation problem rather than a craft one. You are not buying a designer’s eye, you are buying search and a decent setting. For plenty of buyers that is exactly right, and it is honest about being that.

The published route is three steps: choose the stone, choose the setting, and their jewellers make it. Most people do the filtering online first, then book a showroom or video appointment to see shortlisted stones side by side, which is the part that actually matters and the part a website cannot do.

Published starting prices are around £1,789 for engagement rings and £763 for eternity rings, though the odd decimals indicate live currency conversion so figures move. They have a proprietary cut called Cupid’s Ideal, and offer both natural and lab-grown.

Free resizing within 60 days and 30-day returns. It is a second-floor showroom by appointment, not a shopfront, so you cannot browse from the street. Production timescales are not published.

Google shows 820 reviews. Of the 800 we analysed, 707 are five star against 50 at one star, gathered over more than eleven years. That is a solid but not spotless picture, and the one-star share is higher than most jewellers here.

The praise clusters unusually around what happens afterwards: 62 reviewers mention aftercare and resizing, more than mention anything else, which for a company built on inventory rather than craft is a genuinely good sign. Fifty-eight mention diamond knowledge and 36 being given time with questions.

The criticism follows the same shape as elsewhere in the trade: 11 mention delays, seven raise quality or workmanship, six describe refund difficulty. Nothing here suggests a systemic problem at this volume, but it is a visible minority rather than a clean sheet. They reply to 59 percent of reviews, which is among the higher rates we counted and means you can read how they handle a complaint.

Review figures taken from Google and checked in July 2026. We recount them monthly.

This suits a buyer who knows, or is willing to learn, what specification they want and would rather search a huge inventory than be shown a tray. If you have decided on a particular carat and clarity combination and want to compare several examples of it in one sitting, nothing else on this site comes close.

It also suits anyone who wants Mayfair convenience without a Bond Street brand premium, and who is comfortable that the value is in the stone rather than the name.

It will not suit you if you want a designer’s point of view, a one-off setting, or a shopfront to wander into. It is also not the place if you would rather someone narrowed the field for you, because the breadth is the product and it can be overwhelming.

How much do 77 Diamonds engagement rings cost?

Published starting prices are around £1,789 for engagement rings and £763 for eternity rings. The figures carry odd decimals because they are converted live, so expect them to move slightly.

Do I need an appointment at 77 Diamonds?

Yes. The Mayfair showroom is on the second floor of 3 Hanover Square and works by appointment, generally Monday to Saturday 10am to 7pm. Virtual appointments are also available.

How many diamonds do 77 Diamonds have?

Around 1.8 million certificated loose stones, filtered online by cut, carat, colour and clarity. It is by a wide margin the largest inventory of any jeweller featured on this site.

Can I return a 77 Diamonds ring?

They offer 30-day returns and free resizing within 60 days. Six reviewers out of 800 describe difficulty with refunds, so keep your paperwork and confirm the terms that apply to your specific order.