A four-generation family of London diamond experts

Sell your diamonds with people you’d send your aunt to.

GIA member. Rapnet trader. Fifty years’ experience. Instant online estimate, free insured collection, payment within 24 hours.

Get an instant estimate →
How it works

★ 4.9 / 5 Trustpilot

Feefo Platinum

GIA Member

Rapnet Trader

BJA Accredited

Est. 1976 · Family-run

What we buy

Six categories. One standard of service.

Whether it’s a single inherited ring or a parcel of certified stones, every item is examined in person by a named member of our family team.

Diamond engagement rings

Diamond engagement rings

GIA-graded centres, branded settings
Loose diamonds

Loose diamonds

Single stones and parcels
Certified diamonds

Certified diamonds

GIA · IGI · HRD · EGL
Branded jewellery

Branded jewellery

Cartier · Tiffany · Graff · Bulgari
Luxury watches

Luxury watches

Rolex · Patek · AP · Cartier
Uncertified & inherited

Uncertified & inherited

Examined in person, fairly priced

How it works

From your front door to your bank account, in four steps.

01
Get your estimate

Use our calculator or send a photo on WhatsApp. We respond within an hour.

02
Free insured pack

Royal Mail Special Delivery, fully tracked, up to £2,500 cover.

03
We confirm our offer

We grade your stone and call you the same working day.

04
Paid in 24 hours

Bank transfer or cash by appointment — your choice.

Or bring your item to our Hendon Lane office by appointment — same family, same service.

Why a family business matters

Four generations. One family. Fifty years of diamonds.

Rebecca, Jonathan’s daughter, is the fourth generation of our family to work in the diamond trade. We’re not a buyer-of-the-week and we’re not anonymous behind a brand. Every offer is made by a named family member — and stands behind a name.

Jonathan has been a GIA member for over 25 years and trades daily on Rapnet, the global diamond price benchmark. That direct trade access is why we can pay the right price the right way.

Meet our family
Jonathan and Rebecca at their Hendon Lane office

In our clients’ words

Trusted at the most important moments.

★ 4.9 412 reviews on Trustpilot
“I was nervous about posting my late mother’s ring but the process was seamless. Jonathan called within an hour of receipt with a fair offer. Money in my account the same afternoon.”
Helen M. · March 2026
“Got three offers for my GIA-certified solitaire. HowCashForDiamonds beat the others by nearly £400 and paid faster. Genuine experts.”
David R. · February 2026
“After my divorce I dreaded selling the engagement ring. Rebecca handled it with such kindness. Felt like a family conversation, not a transaction.”
Aisha K. · January 2026

The diamond calculator

How much is your diamond worth?

Our calculator is based on GIA Triple-Ex, Nil-Fluorescence pricing, refreshed against current Rapaport-derived market prices. No personal details required to see your number.

Open the calculator
Indicative
£4,200 – £5,400
1.00ct round brilliant · F colour · VS1 clarity · GIA Triple-Ex
Indicative buy-back range. Final offer confirmed in person and depends on cut grade, fluorescence and any treatments.

Common questions

What clients ask us most.

The wholesale buy-back value of a diamond depends on the four Cs — carat, colour, clarity and cut — together with current Rapaport-derived market prices. As a guide, a 1.00ct round, F colour, VS1 clarity GIA Triple-Ex stone currently buys back in the £4,200–£5,400 range. Use our calculator for an instant indication on your stone.

Once we receive and verify your item we usually call you with a firm offer the same working day. Payment by bank transfer typically lands within hours of you accepting. Cash payment is available by appointment at our Hendon Lane office.

Yes. We send a pre-paid Royal Mail Special Delivery pack with £500 standard cover. You can top this up to £2,500 at the Post Office for £3 — we strongly recommend doing so for higher-value items.

Yes, we welcome uncertified and inherited diamonds. Our team examines each stone in person and prices it on the same trade fundamentals we use for certified goods. There is no fee for examination and we return any item you decide not to sell, free and fully insured.

We return your item free of charge by fully insured Royal Mail Special Delivery — no questions asked, no obligation. The whole process is risk-free.

Yes. Jonathan Williams has been in the diamond trade for over 50 years. His daughter Rebecca is the fourth generation of our family to work in jewellery. Every transaction is handled by a named member of our team.

See all FAQs