Situated at the heart of the Indian Ocean, separated from the African continent by the Mozambique canal, the island of Madagascar is one of the earth's paradises for the gemmologist and the lover of precious stones.

A chain of mountains and a volcanic massif runs across the island that stretches over a ribbon of 1,600 km long by 500 km wide. Apart from an important agricultural production, the underground is rich in mica, graphite, gold, chromium and especially in precious stones: rubies, sapphires, beryl’s, alexandrite’s, topazes, zircons, tourmalines, amethysts as well as in quartz, lemon quartz...
In the various sites on the island, there is the Ambanja deposit and its magnificent démantoïde garnets, ranging from yellow green to blue green, but also other garnets ranging from brown red to brown. Some stones are bicoloured ones, but they more than anything else have an exceptional brightness. The first green stones discovered, on the see an edge, were sold as zircons or green sapphires. But the wealthy island also offers emeralds. They are found in schist’s, embedded in gneiss, quartz and pegmatites.
The site is situated in the Manajary region, approximately 250 km from Antananarivo, on the south-eastern coast. The colours of the emeralds vary from pale green to saturated green with a shade of blue. The inclusions are solid and liquid, with veils around the stones. They can vary from one phase to polyphases. Phlogopite, quartz, pyrite, goethite, hematite, barytine are also found in the solid inclusions.
In the north east of the island, a few years ago, fields of rubies were discovered. What followed afterwards was a real rush: more than 30,000 miners flocked to the city of Andilamena to chase the very coveted stone. This great ruby rush may be explained more particularly by the fall in prices at the end of last century, in the sector of fine stones, such as garnets, amethysts, aquamarines and tourmalines. As the miners saw their benefits crumble, they look to the new El Dorado since the prices of rubies did remain stable and even increased in the quality gem.
The production is estimated at several hundreds of kilos from average quality to nice, from 5 to 6 grams (rough) a piece. The largest stones generally have inclusions and glets and are rather planned for the cabochon cut (semi circular) while the smallest (between l et and 5 cts once cut), from nice colour to great clarity, will be faceted in different shapes (oval. marquise, pear, etc,). In the Vatomandry region, the quality is even better, but the stones are of a smaller cut. In the centre of the country, in the Antanifotsy region, a rich mine zone has also been discovered in the alkaline basalt dykes, offering red, brown to purplish rubies, of a homogeneous colour. From quality gem, transparent to translucent, the crystals measure around 3 cm. All the rubies contain inclusions which are evidences of their authenticity and often of their origins. So the rubies originating from Madagascar have typical inclusions that, according to the Güblin laboratory in Luzern, are said to be hematite and ilmenite, instead of the traditional rutile needle found in the rubies of other origins.
Rubies represent only 10% of the gem market in Madagascar, the essential being focused on another precious stone: sapphires. Since 1996, a great production of sapphires has indeed flooded the market. Yellow to blue sapphires, originating from the alluvial deposits of a basalt-magma origin, come from the north of Madagascar. Other fields of multicoloured sapphires have been discovered on the other side of the island, in the south. The Sahambano and Zazafotsy mines, situated in the granulitic region, are metamorphic deposits. The very diversified range of colours may be explained through the presence of iron, titanium, vanadium and chromium in various ratios. Three big deposits are currently being operated: in Diego in the north of Mada, a dark blue sapphire with a shade of yellow green and other colours, such as yellow and green. The site of Ilakaka, in the centre of Mada, 600 km south of Anatananarivo, is the most recognised one, both for the quality of the stones as well as in terms of colours and clarity of the sapphires and it produces sapphires in any and all the colours. " I mainly get my sapphires from this mine, to turn them into rainbow lines, a gradation of any and all the colours. We supply Cartier watch mailing in Switzerland, for instance", says Vincent Livet, the head of Dream Stones, in Antananarivo. Finally, Tamatanve is a deposit which has just recently been discovered: it yields dark blue sapphires of a big size (only recently, a 28-carat stone). It is a mix between the Ilakaka stones and the Diego stones: many dark blue ones with shades of yellow, some with a nice blue, but with inclusions. Unfortunately since all the rubies have small inclusions, they are not guaranteed as authentic. Thanks to the new technologies, the laboratories in the Far East and in Russia manage to create synthetic rubies which are hard to spot out for the neophyte. One of the best guaranties lies, of course, in the certification of authenticity, issued by a recognised laboratory, such as the HRD, SSF or IGI (International Gemmological Institute).