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Ethiopian sapphire: where it comes from and what it is like

Research · · Maedot

Ethiopian sapphire comes from northern Tigray, close to the border with Eritrea. It was found in late 2016, and mining and trading centred on the town of Chila, about 25 km northwest of Aksum. It is a basalt-related sapphire: mostly blue, often dark and rich in iron, and most of it is heated.

Where it was found

Addis Fortune reported in August 2017 that the sapphire was discovered in November 2016 and that mining began five months later, in the Mereb Leke and Laelay Maichew districts. By 2019 GIA reported sapphire from many places across Tigray. Finds have also been reported in Oromia, without production figures.

The geology

The sapphire is linked to alkali basalt, like the deposits of Australia, Thailand and Nigeria. Basalt flows covered an older, hard metamorphic basement; as the basalt weathered, sapphire collected in valley gravels with garnet and zircon. The deposits are secondary, the crystals are rounded, and the gravel usually lies 1 to 3 metres down.

Colour and character

Blue dominates, from dark greenish blue to light blue, with strong blue-green dichroism. Yellow, green and parti-coloured stones occur. GIA found high iron and no detectable beryllium or chromium. In 2017 most rough weighed 2 to 3 grams; crystals over 50 grams were reported, usually cracked. Writing for Gem-A, Simon Bruce-Lockhart put about 90% of the output in the dark, iron-rich group and about 10% as a softer, low-iron mid-blue. GIA's team judged most of the material commercial grade.

Heat treatment

In 2017 GIA estimated that only 5 to 10% of the sapphire needed no heating. SSEF notes that the stones are often dark, sometimes too dark, and are usually heated in Sri Lanka or Thailand to improve colour and clarity. Heating also complicates origin work: it dissolves the rutile silk that laboratories use, and in basalt-related sapphire heating itself is often hard to detect.

How laboratories place it

The first check is the absorption spectrum: like other basalt-related sapphire, these stones show a broad band in the near infrared. SSEF says they are easy to separate from metamorphic sapphire from Kashmir, Sri Lanka or Burma, but closely resemble basaltic sapphire from Rwanda, Nigeria, Thailand and Cambodia. GIA has found clusters of well-formed zircon crystals and multiple intersecting twinning that can point to Ethiopia, but the common inclusions overlap with other deposits. Gübelin Gem Lab compares many observations per stone with its reference collection, and says sources formed in similar rocks can be hard, sometimes impossible, to separate. A report may therefore name Ethiopia, call the stone basalt-related without naming a country, or give no origin.

How it reached the market

Rumours reached the trade in February 2017, and the first stones appeared in Chanthaburi and Beruwala that April. From May, Sri Lankan dealers travelled to Ethiopia to buy, and local prices rose steeply. In 2018 foreigners were not allowed to buy in Chila or at the mines; Ethiopian dealers bought at Chila's Saturday market and sold in Addis Ababa to foreign buyers, mostly from Sri Lanka and Thailand. In the fiscal year to July 2017, Ethiopia exported 31 kg of sapphire for about USD 180,000.

Supply now

Conflict in Tigray disrupted the trade. In November 2022 the founder of a gem business told Ethiopian Business Review that it had run short because it depended on Tigray sapphire. The article also cited Ministry of Mines figures of USD 2.7 million in sapphire exports for the first half of 2021/22. In April 2024 the Ethiopian Commodity Exchange said it was ready to trade sapphire but that security problems, in Tigray among other regions, had held it back. In November 2025 the government again said sapphire would trade there. We have found no later sapphire export figure.

Asking us about sapphire

We offer opal and emerald, and source sapphire on request. A selection lists the stated origin and any treatment or testing on record, including heating.

Sources

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