Demantoid is mined in several countries, but the word Russian in front of it changes the price more than any other word in the description — and it is the part a buyer can least easily check. This page sets out what a Russian demantoid actually is, what to look at before buying one, and how origin is established rather than asserted.
We mine at Korkodin in the Urals and cut what we mine, so the stones described below are the ones we handle daily. Where a figure is quoted, it comes from our current stock.
What makes a demantoid Russian
The stone was first found in the Ural region in 1874 and, by the turn of the twentieth century, had become one of Russia's main gemstone exports. Carl Fabergé used demantoids often enough that the stone came to read as a signature of the period. That history is the reason the trade still treats Ural material as the reference point for the species.
Two nineteenth-century deposits, Bobrovka near Nizhny Tagil and Poldnevo near Polevskoy, were worked until almost nothing remained. The Korkodin deposit, found in the 1980s, is where the market's larger and deeper-coloured Ural stones now come from. It lies beside the Korkodin railway station near Verkhniy Ufaley, about 100 km south of Yekaterinburg, and combines a hard-rock and an alluvial part along a tectonic contact with the Korkodin ultrabasic massif. Elsewhere in the Urals the stones run smaller and paler.
Demantoid also occurs outside Russia — Namibian and Madagascan material has been on the market for years, and it is good material. It looks different, and it is priced differently. If origin matters to you, it has to be documented rather than taken on trust; the section on reports below covers how.
More on the deposit and how we work it is on the page about Demidoff and the Korkodin mine.
The horsetail — the inclusion buyers pay more for
Nearly every other gemstone loses value as inclusions appear. Demantoid is the exception. Fine hair-like fibres radiating from a central point — the horsetail — are the internal feature most closely associated with Ural material, and collectors look for them deliberately. A well-placed spray gives a stone a face no other stone has.
It is worth being clear about the trade-off. A horsetail is still an inclusion: it costs some brilliance, and a stone described as included will read less lively than an eye-clean one of the same colour. What you buy instead is character and a visible argument for where the stone came from. Around 146 of the demantoids we currently hold carry a described horsetail; they are gathered on the page for demantoid with horsetail inclusions, each with photographs.
Reading the colour
Demantoid green runs from a deep emerald tone through to bright golden hues, and sellers describe the same range in wildly different words. We grade our stones into five groups and use them consistently, so that a description can be compared across the catalogue:
- Vivid green — the strongest, most saturated colour, and the smallest group.
- Medium green — the largest group in stock and, for most buyers, the balance between colour and brilliance.
- Dark green — deeper tone; it holds its colour well but returns less light.
- Yellowish green — the classic Ural tone, common in the deposit and often the best value.
- Greenish yellow — golden material, which some buyers seek out precisely for the dispersion.
One property of the stone is easy to miss in daylight photographs: demantoid's brilliance strengthens under artificial light. A stone that looks calm on a desk can be the liveliest thing in the room at dinner. This is why the species was named for its diamond-like fire.
Size, and why large Ural stones are rare
Most Ural demantoid reaches the market small. In our own stock the median single stone sits at about 1.5 ct, with the run of the catalogue between 0.5 and 2 ct. Stones of 5 ct and above exist — we hold around forty at any time, and the largest single stone currently listed is over 20 ct — but they are a different market, and they do not stay long.
Matched sets are quoted by total weight and are the practical route to a pair of earrings or a suite where colour has to agree across several stones. Matching Ural colour after the fact is far harder than it sounds, which is why sets are assembled at the cutting stage rather than from finished stock.
Cut and shape
The round brilliant dominates, and for a reason: it returns the most light and shows the dispersion that gives demantoid its name. Roughly five out of six of our single stones are cut round. Octagon, cushion, oval and princess cuts follow, generally where the shape of the rough makes them the honest choice rather than a stylistic one. Cabochons are the exception — a cabochon is often the right decision for strongly included material, where the horsetail becomes the point of the stone rather than a defect in it.
Establishing origin, not claiming it
Origin is a claim, and claims can be tested. For stones above a certain size we supply a laboratory report; where provenance is the question, a report from a laboratory that issues country-of-origin opinions states the verdict and the reasoning behind it. We have written up three real reports on stones that passed through our hands — GIA, AGL and ICA GemLab — line by line, in the guide to reading a gemstone report. It is the fastest way to learn which lines on a certificate carry weight.
The second answer is structural. Demidoff mines at Korkodin, separates and hand-picks the rough, and cuts it in-house. Nothing enters the chain from outside it. A dealer buying finished stones cannot make that statement, whatever the invoice says.
What is available now
We currently hold close to 450 demantoids — some 390 single stones and around 50 matched sets — all from Korkodin, each photographed with its own colour, clarity, cut and measurements listed. Stock moves, so the catalogue is the accurate picture:
- The full demantoid collection — single stones and sets, filterable by colour, clarity, shape and weight.
- Stones with horsetail inclusions — the collectors' group.
- How to read a gemstone report — what a laboratory does and does not tell you.
If you are looking for something specific — a weight, a colour, a matched pair — tell us what you need and we will say plainly whether it is in the ground, on the cutting bench, or not something we can promise. We also show at international gem shows through the year, where the stones can be seen in person.