Bespoke, made-to-order engagement rings, hand-made in London, exclusively for conscious connoisseurs. 

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uniting true luxury with absolute sustainability 

An engagement ring is unique and special. Our clients are conscious connoisseurs, and we love to delight them.


Our ultra-luxury engagement rings are completely ethically sourced


Our mined diamonds do not solely rely on the Kimberley Process. (The process is a flawed scheme designed to eradicate blood diamonds). We vet our suppliers, and are not afraid to make changes.


We are the UK's leading experts in luxury lab-grown diamonds


Our lab-grown diamonds are completely removed from mining. Yet some diamond growers produce luxury diamonds, and some do not. We refuse over 99% of all diamonds, because they fail to meet our standard.

We exclusively use Fairtrade and recycled metals

previous commissions


how we make your ring

our philosophy


The formidable beauty of an LMK diamond is the result of our intense compulsion to source only the most perfect ethical diamonds available. Discover the perfect diamond for you.


We create a unique, bespoke engagement ring design, perfectly tailored to you. Your design is one-of-a-kind, and we never replicate the exact-same design twice.


Your hand-crafted engagement ring is lovingly packaged in our luxury box and securely delivered, anywhere in the world, ready for the proposal to end all proposals.

About Lydia


I'm Lydia, I'm an ethical diamond dealer and a luxury jeweller. I'm also the UK expert on lab-grown diamonds. My mission is to transform luxury in a truly meaningful way.


I have a background in mining. Transitioning from mining into jewellery was easy - I’m creative with a strong aesthetic. I have an incredible manufacturing team - they have all held contracts at De Beers, Cartier, Boodles, Graff, and Tiffany.


After what I've seen and heard, I didn't want to support 20th century mining practices. It makes no sense for the changes we need to make as a species.


Having said that, I want luxury, love, and abundance. I love beautiful things. Today, we have the technology and raised awareness to unite them.


We have to transform the way we buy, live, and our values. We can't do that if we only inspire a handful of people to be perfect. We need a critical mass making an impact in their own sphere of influence. My sphere is luxury diamond jewellery.

About You


My clients are connoisseurs in multiple arenas and understand how to buy fine wine, antiques, and art. They are successful individuals who recognise that they can enjoy luxury and make a positive impact.


They are patient, and prefer handmade gifts according to their individual requirements, as opposed to those available for just anyone to purchase.

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Tel: 0208 29 555 46 | Email: | Marylebone, London

Unusual engagement ring

This unusual diamond engagement ring design starts at £2,500.