In addition to pegmatite, which are the host rocks of emerald and other kinds of beryl such as aquamarine, Somaliland has metamorphic rocks that hold nodules of ruby and sapphire.

There is little understanding of its mineral deposits but villagers in Somaliland use primitive tools to dig out a range of gemstones that they offer for sale to dealers locally. When aid officials at the European Community (EC) office in the country’s capital, Hargeisa, first saw the gemstones, they believed they had been stolen from graves. To determine whether these stones came out of the ground or stolen from graves, EC invited a consultant geologist and gemmologist from the University of Witwatersrand in Johannesburg, South Africa, Dr Judith Kinnaird, to investigate.

Dr Kinnaird visited the country twice in the past two years. In addition to identifying gem minerals in the country, she helps local miners distinguish among similar coloured minerals and is working with Progressive Interventions supported by EC funding to help set up a gemmological association and marketing channels for Somaliland’s mineral resources.
The following report was compiled by Jewellery News Asia’s contributing editor, Jennifer Henricus from a presentation made by Dr Kinnaird at the annual conference of the Gemmological Association of Great Britain in London in late 2000 and from an interview with Dr Kinnaird.

Somaliland is part of the Mozambique belt and prior to the continental drift 900 million years ago, was in the same area as Madagascar, Tanzania, Sri Lanka and India, Dr Judith Kinnaird said.

Somaliland has the similar type of gem minerals as these other well-known gem-bearing countries but gem deposits have only recently been discovered. Recovery of gemstones, carried out in a primitive and haphazard manner, has been done only since 1988, Dr Kinnaird said.
The gem-producing belt is a fairly narrow strip located in a zone of rocks roughly parallel to the Gulf of Aden and is between 30 and 80 kilometres wide, 200 to 300 kilometres long.

The country was a British protectorate from 1886 until it became independent in 1960 and five days later became part of Somalia, a former Italian colony. In 1982 civil war broke out and lasted for nine years, but the country is still trying to recover from the ravages of this war. “Access to gem deposits is difficult. The debris from the war remains: roads suffered extremely, bridges have been bombed out. Getting to many of the mineral locations involves a bone-shaking journey,” Dr Kinnaird said.

The terrain in Somaliland is varied including high mountains and beaches along the Gulf of Aden. Temperatures are sub-Saharan, up to 50 degrees Celsius in summer on the coast, she said.

EMERALD
The country has two known emerald producing areas, one at Alihiley and another at Simodi in western Somaliland, Dr Kinnaird said.

Emerald deposits occur at the contact of two rock types: where large granite-like pegmatite comes in contact with softer black schist.

Dr Kinnaird explained: “Two types of rock are necessary to form emerald. To give the emerald its green colour, the beryl needs to be in contact with chromium-bearing rock or, in some cases, vanadium, and this colouring agent comes from schist because pegmatite has no chromium.

“Occasionally little fingers of pegmatite go out into the schist and the best emerald rough is in these fingers. Because the schist is softer than pegmatite, most of the exploration work has been in the schist, which is easier to mine. As a result, the miners were going away from the emerald.”

She said in most of the emerald rough she examined there is quite patchy colour development, and the very well developed crystals have a dark green outer layer and a paler or yellowish green core.

Dr Kinnaird said the Simodi area has enormous potential: pegmatite is abundant and is visible in white streaks across the hillsides and on several occasions large clumps of emerald or beryl of other colours have been found.

“The pegmatite in Simodi is located in remote area and it took us six hours to cover 50 miles, with the last two hours spent on foot through the mountains.”
Local miners have recently re-started mining with 200 men working the area after a long period of absence. “They are working on only one pegmatite. Pits were dug in a haphazard manner initially in 1988 during the civil war. The precarious pits will sooner or later become the cause of accidents. I hope to return to Somaliland and try to help organise the mining in the area. The instability of the slopes is aggravated by torrential rain as well as slight earth tremors as the Gulf of Aden is widening.”

She said mining is extremely difficult and painstakingly slow because people do not have the proper equipment. “Rock breaking is done by hammer and chisel while waste is extracted and thrown up by hand in small pans. They have a local saying ‘everybody must put their hands to work’.

“As mining started only recently, gem material is not available in large amount. But inevitably out of every pocket and hut comes some material. Some nice-quality emerald is being mined and people are managing to sell, though in an amateur manner.”

Dr Kinnaird said Alihiley too has some emerald-bearing pegmatite and this is the only place in Somaliland where any sort of mechanical equipment is used. “These miners were the proud owners of a compressor.” She said she had some stones cut and the colour and quality is good.

AQUAMARINE AND OTHER BERYLS
To the east of the emerald gem belt in western Somaliland, the gemstones occur still in pegmatite and they can be seen as white criss-crossing bodies on the hillside. In this eastern part, miners are working on pegmatite with aquamarine, Dr Kinnaird said.

“Because the pegmatite has intruded into a granite rock, it does not have chromium to give the beryls the green colour. Instead, the presence of iron or titanium gives forth the blue or blue green colours of aquamarine.”

Dr Kinnaird said the aquamarine crystals in the area are quite large. “I have seen crystals up to one metre long, but the crystals are mostly characterised with cracks. The local miners thought they were actually creating the cracks because of the lack of proper tools. It was a surprise to them to realise that a lot of the material is originally cracked although the lack of proper equipment does add to cracks and fractures.”
However, it is possible to produce nice polished of good colour from these crystals, she said. There have been reports of yellow beryl or heliodor also being mined in the area as well.

RUBY AND SAPPHIRE
Ruby and sapphire occur in the gemstone belt, in metamorphic rock instead of pegmatite. A nice bright red ruby, similar to ruby from Longido in Tanzania, has been found in a metamorphic rock. The ruby occurs as core of red corundum together with green zoisite.

Getting to the ruby deposits in the Molis area is difficult, Dr Kinnaird said. “The usual mode of transport for food and goods in the area is on camel back. In addition, residents in the area treat outsiders with great suspicion, which is a legacy of the civil war. People in the area belong to different clans and are suspicious of people from other clans.

“To get to the area, one needs an escort from the right clan and permission from the Ministry of Water and Minerals. Because of the mistrust and suspicion among the inhabitants, it is difficult to get to the gem bearing areas,” Dr Kinnaird said.

Sapphire occurs in nodules on the surface. The nodules appear as lumpy bumps of corundum, and when cracked open, expose the sapphire. Nodules on the surface produce a more greenish blue sapphire, but nice blue sapphire is being mined from greater depths within the rock.

The deposits in Somaliland are different from those in other African countries such as Tanzania and Nigeria where both sapphire and ruby occur together. In Somaliland, ruby and sapphire are found separately.

GARNET, OPAL AND QUARTZ
Dr Kinnaird said the most abundant mineral in Somaliland is garnet. “Everywhere I went there were garnets by the bucket loads - garnets in varying sizes and colours from red to orange, grossular garnet, pyrope and almandine garnets. When polished, they are clean and beautiful.

“When I showed Tsavorite garnet from Kenya to some miners, they said they had seen green garnet and took me to see their green garnet. The rock formations resemble the Kenyan area bearing Tsavorite garnet. We found a few tiny crystals. The larger green crystals which they believed to be green garnet turned out to be a minty green vesuvianite.”

Dr Kinnaird said in the places she went, people showed her crystals and wanted her to help identify the stones. “One of them was my driver who brought me orange to yellow opal which did not have a good play of colour. I have also seen nice reddish material with a good colour play and it seems that there is an abundant supply of opal in the country.

“When I first saw the opal specimens, I thought because they looked like the opal from Ethiopia they might occur as nodules in rhyolite. However, some of the opal appears in gypsum and anhydrite strata near the coast of Berbera, although the opal from the west of the country may still come from lava.”

Dr Kinnaird said Somaliland has an abundant supply of a variety of quartz. She said an area to the west of Darbuuruq was mined in 1977 and 1978 and a Bulgarian company extracted some 200 tonnes of rock crystals of high purity and clarity. There is also a variety of smoky quartz, often banded, as well as a good quantity of amethyst in deep purple.

Dr Kinnaird said there is production of red spinel and tourmaline in dark green and pink watermelon type, which the miners initially mistaken as alexandrite. An abundance of zircon, nice crystals of colourless topaz, blue and green vesuvianite, rarer titanite as well as apple green apatite occurs in abundance in the emerald-bearing localities.

She said many thought the quartz was diamond and it requires a lot to explaining that there are no diamonds in Somaliland.

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Source: Waaheen

 
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