JNJ Precious Stones curates and trades investment-grade coloured gemstones and diamonds — from Burmese pigeon-blood rubies to Kashmir sapphires — for a discerning global clientele.
Every piece in our inventory passes a four-stage authentication, grading, and provenance review before it is offered. A curated preview below — the full collection is available to registered clients.
Velvety cornflower-blue sapphires from the legendary Padder Valley mines. Extreme rarity, exceptional saturation.
The finest Burmese rubies with the signature fluorescent red glow. Untreated, with GRS and AGL certification.
Vivid grass-green emeralds with the coveted "jardin" inclusions that confirm Muzo provenance.
Neon electric-blue tourmalines coloured by trace copper. Among the most sought-after gems in the world.
The lotus-flower sapphire — a delicate blend of pink and orange hues, named after the Sri Lankan lotus.
VS-clarity fancy intense yellow diamonds, GIA-graded. Ideal for statement center stones.
Direct trade in certified loose coloured stones and diamonds for jewellers, auction houses, and private buyers.
We locate stones to exact specification — size, hue, origin, certification — drawing on three decades of trade relationships.
Independent in-house valuation for insurance, estate, resale, or acquisition — signed by our qualified gemmologists.
We submit stones to the leading laboratories worldwide and manage the certification pathway end-to-end.
Confidential advisory on investment-grade acquisitions, estate dispersions, and long-term portfolio strategy.
Fully-insured bonded transit worldwide. White-glove handling from vault to buyer with real-time chain-of-custody.
For twenty-seven years JNJ has operated on a single principle: the gemstone in your hand must be exactly what we said it was, from exactly where we said it came from.
Every stone we place is accompanied by independent laboratory certification, a chain of provenance, and a fair-market valuation. We trade with jewellers, collectors, auction houses, and family offices across four continents.
Our StoryJNJ sourced a 4.8ct Kashmir sapphire for a private commission that three other traders had told us was impossible to find. Flawless provenance, fair price, and delivered in six weeks.
Share your brief. Our specialists will respond within one business day — in confidence.
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