Our story
Built for people who take gemstones seriously.
Rhea Cylone was founded on a simple conviction: every stone deserves an honest record. We are a specialist vault — not a marketplace — where each gem is independently graded before it is ever shown to a buyer.
Insured shipping to 42 countries
Shipped & insured to 42 countries
Door-to-door, fully tracked
Customs & export paperwork handled
CITES and duty documents included
Independent grading on every stone
NGJA
Our vision
A world where every gemstone speaks for itself
We envision a gemstone market where price reflects quality, quality is independently verified, and every buyer — from first-time collector to seasoned investor — has access to the same unambiguous data that experts have always kept to themselves. Transparency is not a feature. It is the foundation.
Our mission
To list only what we can fully account for
Our mission is to operate the most rigorously documented gemstone vault available. Every stone we list carries an independent laboratory report. Every treatment is disclosed. Every origin claim is sourced from that report — not inferred from colour or cut. We exist to eliminate the information asymmetry that has disadvantaged buyers for too long.
How we do it
Independent grading, without exception
No stone is listed before it is graded by NGJA. We do not grade in-house, and we do not list a stone against a report issued to a different stone. The report number on the page is the report number in the parcel.
Treatment disclosed, every time
Heat, oil, fracture filling and diffusion each change value materially. Where a laboratory records a treatment, we print it on the card, the detail page and the invoice. 'Unheated' appears only where the report says so.
Origin where it can be evidenced
Country of origin is a laboratory opinion based on inclusion and trace-element analysis. We state the country the report names. Where origin is inconclusive, we say so rather than inferring it from the colour.
Natural and lab-grown, clearly separated
Lab-grown stones are labelled at every point in the interface and priced against lab-grown comparables. They are never presented alongside natural material without that distinction.
Every stone is examined before it's listed — not photographed and described from a supplier's own notes.
Ready to explore?
Enter the vault.
Browse 100% natural, certified stones with full origin disclosure and independent laboratory reports — no guesswork, ever.
100% natural gemstones
Insured worldwide shipping
Secure escrow payment
Independent lab reports
Independently graded
Every stone ships with its NGJA report.
Insured to the door
Fully insured, signature-required transit worldwide.
Negotiable
Prices are negotiable — reach out and we'll respond within 24 hours.
Escrow above $50,000
High-value settlements held until you accept the stone.