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[Fiebre Verde]

Dolomite crystal and emerald cluster over a white calcite rhomb.

[Fiebre Verde]

Main crystal is double terminated.
Host rock is black shale.

[Fiebre Verde]

In September 2015, the UK-based mining company Gemfields has entered into binding agreements to acquire controlling interests in two emerald projects in Colombia, one of them being Coscuez. At completion, Gemfields will acquire an indirect 70% interest in a Colombian company which will hold the mining contract for the Coscuez mine.
It's still too early to measure the impact of this major takeover on the specimen production from this historical mine.

[Fiebre Verde]

Not the most aesthetic specimen of my collection but probably the most exotic one.
I found this specimen in a European show, 7 years ago. The label mentions Peñas Blancas for the locality name but nothing is less sure.

Assuming it's not a fake (which is a reasonable assumption considering the poor quality of the apatite crystals and the way they are contacted by the emeralds from almost every side), here is the dilemma:
1) The only Colombian locality producing/having produced pink tabular apatite is La Marina mine which is located right in the heart of the Western Emerald Belt.
2) The Mindat mineral list for La Marina is limited to albite, euclase and apatite. Never heard of any emerald occurrence in La Marina, even from the most enthusiastic dealers in Bogota (I like to challenge them but that's another story...)

Of course, the other option is that it's not Colombian.
It is reported that pink apatite, beryl (variety emerald) and albite (variety cleavelandite) can be found in the Laghman pegmatite province in Afghanistan. But Laghman province is vast and these minerals do not necessarily coexist in the same locality. Not even mentioning that Laghman emeralds are known to be embedded in schist matrix.
So Laghman is a very remote possibility...

In the absence of further evidence, I will label this specimen as Colombian.

Matrix is highly oxidized albite.

[Josele]

Really an interesting piece!

A quick search in mindat gives more examples of Colombian emerald-apatite combinations:
https://www.mindat.org/photo-66089.html
https://www.mindat.org/photo-66130.html

If it is not Colombian, could be also from Pakistan.

Did you check the fluorescence?

[Fiebre Verde]

[Fiebre Verde]

Fine beryl from Coscuez.

[Tobi]

I will never get tired of watching these green gems - please more :)

[Fiebre Verde]

[Fiebre Verde]

A large beryl crystal from El Toro, in the Gachalá mining district.

The El Toro mine is located next to the Matecaña tunnel which is known to have produced in the early 00’s the famous emerald gastropods (BTW, for those interested in this topic, some very interesting discussions and photos can be found in this forum).
The material produced from El Toro is frequently coated with a thin film of brown limonite which gives a stunning copper iridescence. In Gachalá, the limonite is formed from the weathering of pyrite.
Obviously the limonite coating has been removed from the beryl but not from the surrounding quartz crystals which I think, improves the overall aesthetic of this specimen (and incidentally makes the photographer’s life much easier).
In the future, I will post more specimens from El Toro where the film of limonite has been completely removed.

Out of all the El Toro crystals I have seen, the vast majority were light green and opaque. This one has a good luster and some degree of transparency in the upper part.

[Fiebre Verde]

Another specimen from an unknown locality of the Gachalá district.
The beryl crystal features 2 planar surfaces, a light green surface and a dark green surface.
The light green one is actually a contact plane.
The darker one is a bit more challenging - the step-like tabular patterns might suggest that the whole surface is actually a system of complex terminations.
I have never seen anything like this at this scale - looking for your suggestions and ideas!
Sorry for the quality of the close-ups - I tried again and again, but could not get anything better :-(

Host rock is black shale.

[Fiebre Verde]

Aggregate of 5 crystals from the La Pita district - all double terminated.
Host rock is black shale.

[Fiebre Verde]

The iron-stained creamy calcite combined with the clear quartz and the velvety blue-green emeralds makes this specimen unmistakably from Peñas Blancas.
The calcite and the emeralds are dusted with brownish-black goethite.
Host rock is black shale.

[Fiebre Verde]

Coating of botryoidal white calcite with clear quartz crystals.
Host rock is fine-grained argillite shale.

Peñas Blancas is the northernmost locality of the Western Emerald Belt.
It's located about 10km north-northeast of the Coscuez district.

[Fiebre Verde]

Host rock is fine-grained grey shale.