Safari njema Tanzania - Mwajanga, a new deposit for tourmalines

For several years, a small settlement called Mwajanga has been delivering tourmalines, some of which are spectacular. While this occurrence was almost unknown when I first visited it in 2011 and there were no hits on Google, this has changed drastically in recent years, especially with the discovery of magnificent chrome dravites in 2016. This deposit is always good for surprises. With many visits

the heaps of white marble and muscovite, gleaming brightly in the sun

in recent years there has always been something interesting and new.

Mwajanga is located in the SE of Arusha near the small Masai settlement of Komolo, about 16 km away on the edge of a range of hills. These mounds are formed in part by white dolomite marble, which in turn contains pegmatite veins with much muscovite. It is very interesting that at the beginning of the mining activity "only" Fe-Dravite was found (probably also in very beautiful yellow and brown crystals of faceting quality), but these were often found in and on snow-white natrolite crystals, an unusual paragenesis.

a beautiful specimen of dravite crystals set within and on natrolite, a fairly rare paragenesis

The hills around Mwajanga are now riddled with tunnels and shafts, we call this "foxhole mining" and this method led to the discovery of new tourmalines, also of faceting quality.

a very beautiful yellow dravite, transparent a deep brown Fe dravite

In recent years, the number of Tanzaniers working there must have been around 120 people. Since the shafts and tunnels are scattered in the bush, a precise overview is not possible. The mining is mostly financed by well-off mineral traders from Arusha.

In July 2014, a pocket with multicolored, mostly yellow, long-prismatic tourmaline crystals was unexpectedly opened. Analysis courtesy of Josh D.Lents (private communication, Gemological Appraisal Laboratory of America, Inc in New York) determined it to be elbaite. Almost all of the crystals have pale blue top surfaces, while pink, red and yellow zones alternate on the inside.

a large yellow elbaite crystal from the pocket of yellow tourmalines

According to the mine owner, the total yield of the pocket was about 7 kg of tourmaline, of which about 3 kg were very good crystals of 2 g to 400 g each. The rest were crystal fragments.

Another tourmaline variant found in Mwajanga in the early years is a completely colorless tourmaline called "achroite". As far as I know, these always came loose and extremely rarely with heads and have not been found for about 3 years

some of the colorless tourmalines ( achroite ) found only for a short time, the middle one with end surfaces

After all the finds of different tourmaline variants one could expect more from this deposit and so it happened. In November 2016, beautiful chrome dravites similar to those found in the classic Landanai deposit in nothing inferior.

the shaft of the Kamana pit where fantastic chrome dravites were found in 2016

Unfortunately, unfortunately, this find happened 2 months after our visit and unfortunately all the really good crystals were completely bought up by two dealers (an American and a white-skinned Tanzanian), so that only the leftovers were left for others. But that's how it is now

two chrome dravites from the Kamana pit, very nice to see the pleochroism of the dravites

you also need luck to be in the right place at the right time.

The last big find, again a new variant of the tourmaline, was made in spring 2017. A large pocket with multicolored tourmalines was opened. Almost all have an inky blue head with good end surfaces

one of the rare double ended, blue head, yellow-green opposite side, colorless to dark brown in the middle

below a colorless zone, followed by an almost black part and the lower part yellow-green. Double ended, like the crystal above and/or specimens in matrix are extremely rare and also highly coveted (this time we were there and were able to acquire a large part of the find).

the largest double ended crystal in matrix from the pocket of 2017

However, all of these crystals are opaque.

Another mineral that was often found in the early years are large green, partly transparent, apatite crystals. However, these have not been on the market for about 4 years.

There will certainly be some surprises from this deposit in the future, one reason why we visit Mwajanga every year.

Finally, a little something: there are not only interesting tourmalines, but also exciting plants. This is how these pretty hemp plants grow on the heap and are also harvested well.

after a hard day's work in the tunnel, a bit of "tobacco" wouldn't hurt, marijuana on the heap

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