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| Sapphires from Andranondambo, discovered in 1991. ( South-Eastern Madagascar )
  
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In 1658, Flacourt, the governor of Fort-Dauphin, mentions
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| sapphires in southern Madagascar. |
| In 1808, Barthélemy Hugon writes that in the valley of |
| Ambolo there is a so beautiful stone and so rare that his |
| lapidaries have not been able to recognize it and it was |
| above of all that is not diamond. ... In 1991, at the time of |
| the great dryness in the south, sapphire samples are found, |
| several centuries after their first discovery. The son of Mrs. |
| Dauphine, innkeeper in Tranomaro, main village of the |
| valley, was among the prospectors. |
| Actually, one of the most beautiful sapphire quality in the |
| world is just leaving ground. |
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The Tranomaro area is characterized by an |
| extreme calcic and magnesian paragneiss abundance: |
| Gneiss with diopside, plagioclasites, pyroxenites, |
| wernerites, wolastonite marble, with varied |
| leptynites, generally with garnet, kinzigites, quarzites. |
| One finds there rather frequently syenitic gneisses |
| or lamboanites. Gneisses of injection are very |
| frequent. |
| The typomorphic minerals are: basic diopside, |
| scapolite, calcite, plagioclases, |
| wollastonite, garnet, cordierite and corundum. |
| East of Tranomaro, arteritic and eyesys injections |
| assign gneisses at leptynites. Cordierite gneiss stripes |
| are deeply injected bed by bed, the injection has |
| introduced magnetite in abundance. |
| Wollastonites form ptymatic lenses with |
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Marohotro, 8 km. south of Andanondambo. |
folds very tortured at the middle of the limestone. |
| The sapphire on the left comes from Ambandanira, and |
Note:aluminous anorthites or sakenites. |
| that on right-hand side from Maromby |
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| (area of Andranondambo) |
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Holes can reach 20 meters depth. |
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| Sapphires from Ilakaka. |
One of the various holes in sandstone forming |
| ( South-Western Madagascar ) |
the deposit of Ilakaka discovered in to 1998. |
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| Blue sapphires , pink and violet, Ilakaka area. |
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ISALO SANDSTONES. |
| The white sandstones of Isalo present imposing |
| stratifications intersected with gravel beds and |
| small conglomerates. |
| These soft sandstones resisted to erosion and taken a |
| ruiniform relief because the presence of braces siliceous |
| veins. |
| The mineral-bearing deposits include : a deposit of generally |
| classified gravels, the richest part and larger elements |
| being at the base of the bed - rock. |
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The far-south of Madagascar, semi-desert, does not present |
 Polychrome sapphires from Iankaroka |
| any asphalt road yet, dust and trepidations are the daily |
| discovered in 1990. |
lot of any traveller. Sunsets and the natural life of its |
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inhabitants offer an appreciable compensation. |
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| This sapphire occur in a contact |
| zone between granites and |
| migmatites. |
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| It is found in its bedrock. |
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| Rubies from Ianavoha. |
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| (Southern Madagascar.) |
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Rubies in syenite from Andranomilitsy. |
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| Ruby from Andranomilitsy (Vohitany) |
Syenitic-nephelinic vein of rubies in Andranomilitsy. |
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In Soamiakatra, rubies were sold with sunglasses. |
The Mayor of Soamiakatra in 1989, (East of Antsirabe.)
Rubies from Soamiakatra in the highlands.
Here, rubies are always found in alluvium.
MADAGASCAN CORUNDUMS
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| Ambondromifehy ( Diego ) |
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| BLUE SAPPHIRE NATURAL COLOR |
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| Sapphire from Analafady (Ambondromifehy) North. |
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| The Ambondromifehy alluvial deposit is exploited since |
| 1996. It is located in a Jurassic limestone, but the origin of |
| sapphires is in alkaline basalts from the close volcanic zone. |
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Mahatsara ( Ambondromifehy) |
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The consumption of khat “a kind of narcotic plant” is quite
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common in the Diego-Suarez region, people can be very
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| dynamic. |
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| This deposit produced mainly blue sapphires, but also some |
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| bi-color, some yellow sapphires, and rough material to cut in |
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| cabochon and, star sapphire too. |
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| Didy Sapphire & Ruby Rush 2012 |
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| Within 2011, sapphires from Ambatovolana reached |
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| the capital Antananarivo sporadically, brought there |
| by gold miners. |
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| Ambatovolana is located 25 kilometers south-east of |
| the village of Didy, which is located 45 km.south-east |
| from the town of Ambatondrazaka. (Tamatave region.) |
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| On July 18th 2011, a lapidary from the Capital reveals to |
| me that the extraordinary sapphires in his hand come |
| from "Ivoloina" a new deposit located in the region of |
| Brickaville, on the road to the port of Tamatave |
| (Toamasina.) I buy the stones. |
| But it was not the truth. |
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| " The deposit on the Ivoloina river is actually located 40 |
| kilometers from Tamatave." |
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In the beginning of 2012, a sapphire and ruby rush occurred |
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due to the exceptional color, clarity and size of the precious |
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stones found there. |
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Discovered in alluvium, in the core of a wild forest, sapphires |
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and rubies required holes from 50 centimeters to 2 meters |
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depth only to be extracted. |
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| Paper written by the cutter. |
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| Alaotra formations: |
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| Crystalline schists: |
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| The petrographic bottom is characterized by an abundance of pyroxéno- |
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| amphibolic formations in a set in which gneissico-migmatitic rocks are |
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| found as follows: |
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| - The gneisses at hypersthene are well represented on the North and |
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| East bank of Lake Alaotra: |
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| - Amphibolites and shale feldspathics pyroxenites appearing frequently in |
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| patches or enclaves to form heterogeneous migmatites of épibolites type |
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| (rocks consist of interbedded veins of aplites beds per bed). |
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| - The amphibole gneiss, amphibole and biotite, or biotite alone can pass |
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| locally to banded migmatites. |
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| - Locally surmicaceous gneiss and mica becoming micaschists and containing |
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| shreds of muscovite mica schists between the rivers Onibe and Ivondro. |
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| - Finally, beds of quartzite or magnetite quartzite distributed of very irregular |
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| manner : magnetite quartzites show a bigger development in the region of |
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| Imerimandroso and Andilamena peninsula, on the shores of Lake Alaotra; |
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| white quartzites more or less crystallized are quite rare and form thin beds. |
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| We can distinguish an aluminous series and calco-magnesian series. |
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| Alumino-silicate series is not uniformly distributed, but appears quite clearly |
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| located at the base of the group Alaotra. This series is represented by |
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| sillimanite quartzites and gneisses more or less quartzic biotite, sillimanite |
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| and garnet, very often these gneiss are graphitic. |
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| Calc-magnesian series develops on the western bank of the group Alaotra, |
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| especially south of Ambatondrazaka where diopside gneisses and marbles |
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| are of great importance. |
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| - Gabros have a significant development in the group Alaotra, their |
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| main feature is their perfect match with the surrounding formations. |
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©  All of the pictures on this website have been shot by gggems.com |
Your guide to GGGems |
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| Text written by Alain Darbellay. |
Alain Darbellay |
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