Prestige. Provenance. Proven Performance.
Loose Diamonds & Precious Gemstones
Jewellery
Looking to sell a Kashmir sapphire, a Colombian emerald, or a certified D-colour diamond? Regent Street Antiques offers expert-led service and immediate offers on fine diamonds and gemstones — trusted by collectors worldwide.
- Same-Day Instant Cash
- Best Price Guaranteed
-------------- EASY PROCESS
How To Sell Signed and Boxed Jewellery Online?
Fill In The Form
Fill in our online form & get an accurate FREE quote within 24 hours.
Quick Assessment
We’ll thoroughly inspect your jewellery item to make a final offer.
Same-Day Payment
If you accept, we’ll make an on-spot payment. No added fees.
Featured Signed and Boxed Jewellery
-------------- WHY US
Why Sellers Trust Regent Street Antiques
- Specialists in high-value diamonds & rare coloured gemstones
- Same-day offers & immediate payment
- Trusted by collectors across the UK, Europe, and internationally
- Private appointments at our offices or 5-star hotel partner locations
- Secure home visits available across the UK and Europe
Fill in the form to get free quote →
-------------- Sell Your Loose Diamonds & Rare Gemstones with Confidence
The Timeless Allure of Loose Diamonds & Precious Gemstones
Loose diamonds and coloured stones are the ultimate blend of natural wonder and enduring value. Whether held for investment, future jewellery, or resale, high-quality stones — especially from fabled origins like Burma, Kashmir, or Colombia — remain among the most coveted treasures.
Each rare stone tells a story: of beauty forged deep in the earth, of craftsmanship, and collector demand.
Gérard Paris: The Spirit of Place Vendôme Elegance
Carrying the elite traditions of French high jewellery, Gérard Paris became synonymous with magnificent diamonds, vibrant coloured gemstones, and refined yet bold designs. Gérard’s jewels were favoured by royalty, aristocrats, and international collectors who demanded only the very finest.
Each Gérard Paris piece showcases a commitment to excellence, innovation, and timeless sophistication.
The Most Coveted Diamonds and Gemstones We Seek
- Loose D–F Colour, IF–VS Clarity White Diamonds
- Fancy Coloured Diamonds (Pink, Blue, Yellow, Green)
- Burmese “Pigeon’s Blood” Rubies
- Colombian “No Oil” or Minor Oil Emeralds
- Kashmir & Burma Sapphires (Unheated Preferred)
- Ceylon (Sri Lankan) Sapphires
- Paraiba Tourmalines, Alexandrites, and Natural Spinels
- GIA, SSEF, Gübelin, or AGL Certified Stones
Jewellery with original boxes, certificates, and confirmed signatures is especially valuable.
Iconic Gemstones & Diamonds We Seek
- Top-Grade Loose White Diamonds:D–F colour, Internally Flawless–VS clarity, brilliant or old-cut.
- Fancy Colour Diamonds:Natural pinks, blues, greens, and vivid yellows with GIA reports.
- Burmese Rubies:Deep red, unheated rubies from Mogok, highly prized by connoisseurs.
- Colombian Emeralds: Vibrant green, minimal-oil stones from Muzo or Chivor.
- Kashmir & Ceylon Sapphires:Velvety cornflower blues and vibrant untreated Sri Lankan stones.
- Collector Stones: Paraiba tourmalines, alexandrites, spinels — rare gems of high value.
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Why Collectors Seek Loose Stones
- Ultimate Flexibility: Ideal for investment, resale, or custom jewellery.
- Rarity & Provenance: Stones from famed mines or with no enhancement attract global demand.
- Certified Confidence: GIA, Gübelin, SSEF, and AGL reports elevate trust and value.
- Investment Growth: Top-quality stones appreciate strongly at auction and among collectors.
-------------- About Us
About Regent Street Antiques
Regent Street Antiques is a leading international buyer of rare diamonds and coloured stones, from Kashmir sapphires and Burmese rubies to fancy coloured diamonds. Based in the UK and trusted globally, we offer expert guidance, market-leading offers, and total discretion.
Looking to Sell Your Loose Diamond or Gemstone?
We specialise in acquiring exceptional signed pieces:
- Free, confidential valuations
- Competitive offers from true collector demand
- Expert authentication and provenance support
- Discreet, immediate transactions
Testimonials
Discover how knights, nobles & servants lived within the castle’s walls during its golden age. We welcome you to step back in time.
Surrey
Kent
Kent
FAQ's
Frequently Asked Questions
1. Which Cartier watches are most in demand?
3. How can I get a valuation for my Cartier watch?
5. Do you only buy vintage Cartier watches?
No — while we focus on rare and vintage pieces, we also purchase modern Cartier watches, especially limited editions or models with original box and papers.
2. How quickly can I receive payment for my watch?
4. How do I know my Cartier watch will be valued fairly?
6. Can I meet in person to sell my Cartier watch?
Trust & Assurance
Free
Valuations
Private Appointments
(Home/Hotel)
Insured Postal
Packs
Expert Valuers
(30+ Years' Experience)
FGA/DGA Gemologist
On Request
Same-Day Offers &
Secure Payment
Fully Insured Collection
Across UK & Europe
