How origin is determined, and why it moves the price

Yes. Fine Sri Lankan, or "Ceylon", sapphires are valued by the trade, and Sri Lanka ranks with Kashmir and Myanmar among the classic sapphire sources. But origin adds value on top of quality, not instead of it: color decides most of a stone's price, and a dull sapphire from a famous place is still a dull sapphire. And the country printed on a report is a lab's expert opinion, reached by comparing the stone with reference samples. It is not a fact the stone can prove.

How a lab decides where a stone came from

Origin is really a question about geology. Gems form under particular conditions, and those conditions leave traces inside the stone. Labs read the traces in four steps.

1. 1.
   Sort by geological type. Blue sapphires split broadly into metamorphic stones (Sri Lanka, Myanmar, Kashmir, Madagascar) and basalt-related stones (Australia, Thailand, Cambodia, Nigeria, Ethiopia). Rubies split into low-iron, marble-hosted stones (Myanmar, Vietnam, Afghanistan, Tajikistan) and high-iron stones (Mozambique, Madagascar, Thailand and Cambodia). Placing a stone in the right group rules out most of the map.
2. 2.
   Read the inclusions. Under the microscope, silk, particle clouds and mineral crystals form "scenes" typical of certain deposits. A few inclusions are telling on their own, such as tourmaline crystals in a Kashmir sapphire, but they are rare.
3. 3.
   Measure trace elements. Laser ablation mass spectrometry measures iron, gallium, magnesium, titanium, vanadium and other elements down to parts per million. Each deposit tends to occupy its own range.
4. 4.
   Compare with reference stones. All of this is matched against collections of samples gathered as close to the mines as possible and documented for where, when and from whom they came.

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The limits

Every major lab states on its reports that origin is an opinion. There are good reasons for that.

• Deposits overlap. Madagascar, a large producer since the 1990s, yields sapphires that can resemble any of the three classic sources. Some sapphires from Myanmar are virtually identical to some from Sri Lanka.
• Heat erases evidence. Heating dissolves silk, which in many blue sapphires is the only internal feature that supports an origin call. For heated blue sapphire, origin can be challenging or impossible.
• "Inconclusive" is an honest answer. When properties overlap, or match nothing in the reference data, a careful lab says so rather than guess.
• Old rules get revised. Orange fluorescence in blue sapphire was long read as a sign of Sri Lanka. More data showed it also occurs in stones from several other low-iron deposits, so it is now of little help.

Why two labs can disagree

Labs build their own reference collections, and many keep their criteria private, so the same stone can be read differently. There are hundreds of labs worldwide, and many issue origin opinions without the instruments or the experience the work needs. Disagreements are documented. One sapphire sold at auction carried three reports with two different origins, Sri Lanka and Burma; one ruby carried four reports naming either Afghanistan or Vietnam. Auction houses now often print every report and let buyers weigh them.

For an important stone, a second opinion from another major lab is ordinary diligence. So is reading the date on a report: criteria move as new deposits are found.

Why origin moves the price

The trade pays for scarcity and history. The Kashmir deposit was found in 1881 and worked mainly until 1887, so its supply is essentially historic, and a fine Kashmir sapphire can sell for many times more than an exceptional sapphire from Madagascar. Myanmar's reputation for ruby works in the same way.

A rule of thumb from a veteran dealer, quoted in a GIA series on value: color accounts for about 60% of a colored stone's value, origin for about 15%, and cut and size for about 10% each. With a name like Kashmir, origin can count for far more. It can even outrank quality: a lesser Kashmir sapphire may sell above a much finer stone from Sri Lanka.

Three consequences for a buyer:

• Origin needs its own report. A standard identification report confirms what the stone is; it often does not say where it came from.
• A famous name does not rescue a poor stone. Plenty of low-quality material comes from celebrated places, and its origin adds little.
• Where origin adds money, it attracts misuse. Some sellers describe a color with a place name, as in "Kashmir blue", and some Sri Lankan sapphires that look Burmese are sold as Burmese. The trade has a nickname for that: "lucky Burma".

This describes how the market prices stones; it is not investment advice.

The origins buyers ask about

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What Everystone does about it

A lot in the shop shows its origin and marks it either lab-confirmed or declared. Where the lot has a lab report, the record names the lab and the report number, so you can see whose opinion the origin is. You can filter the shop by origin. Every lot also says how far it has been checked, from seller-declared to full verification; we do not turn an origin opinion into a fact. Every purchase is a protected payment, and during the inspection window you can arrange an independent check before your money is released.

To check a report you already hold, start with how to cross-check a lab report.