FMF - Friends of Minerals Forum, discussion and message board

[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.

[Fiebre Verde]

Fine beryl crystals from Chivor.
These complex pyramidal terminations are not uncommon in the Eastern Belt.
I don't have much information on the locality but I would not be surprised if this specimen was from El Oriente mine.

[Fiebre Verde]

This is another example that illustrates the broadness and variety of the Chivor emeralds. Associations, color, termination and crystal form, the Chivor district has a lot going for it!
These emerald aggregates were recovered from a pocket discovered in the late 00's.
Host rock is grey limestone shale.

This specimen is from a locality which does not appear in the list
Chivor mining district, Mina Piedra de Chulo, Municipio Chivor, Eastern Emerald Belt, Boyacá
I would be grateful if a site admin could maybe update the list. Thanks!

[Fiebre Verde]

Host rock is grey limestone shale.

[Fiebre Verde]

A short while ago I had posted a specimen coated with a thin film of brown limonite (February 2).
Here is another specimen from the same mine where the limonite has been (almost) completely removed.

All these El Toro limonite-coated specimens have been recovered from the same pocket in 2008. And because of the limited size of this pocket, handcrafted specimens in the form of intergrown clusters flooded the market in the late 00's. Floaters were simply glued and covered with a film of limonite.

[Pierre Joubert]

Hi Gerard. I find this specimen 'IMG_4240nb.JPG' very interesting.

[Fiebre Verde]

[Fiebre Verde]

A special specimen - each beryl crystal is unique (termination, color, form).

[Fiebre Verde]

Scalenohedral ‘wheat sheaf’ rhodochrosite clusters on a manganite matrix.

All the FMF members who have been silently suffering week after week from the green fever (aka Fiebre Verde) deserve a little break. So let's see life through rose-tinted spectacles for a change.

Today, N’Chwaning rhodos are far much rarer than Colombian emeralds and specimens exhibiting the ‘wheat sheaf’ habit are even more rare.
I wish I could pursue this ‘pink’ mineralogical journey but I’m afraid I will have to move back soon to greener pastures!

[Jamison Brizendine]

Wonderful Rhodochrosite, Gérard!

[Fiebre Verde]