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[Fiebre Verde]

Another specimen from the prolific mining district of La Pita.
Host rock is black shale.

[Fiebre Verde]

This find is from the early days of La Pita where the beryl crystals are often found embedded in the calcite.
Host rock is black shale.

[GneissWare]

Fiebre, Very nice emeralds!

[Fiebre Verde]

Thanks Bob!
Gérard

[Fiebre Verde]

Although one of the known accompanying minerals of emeralds, aragonite is not commonly found.
I have seen less than a handful specimens featuring acicular aragonite - all from the Chivor district.
Matrix is a mix of calcite and grey shale.

[Fiebre Verde]

This specimen is a good example of the material that can be found in Chivor.
Emeralds are shaped like long thin pencil leads and show a strong bluish cast.
Tiny nodules of crystallized pyrite can be seen in the close-up image.
Host rock is grey shale.

These combined characteristics leave little doubt about the origin of this specimen.

[Fiebre Verde]

Nice little aggregate of emeralds.

[Tobi]

GORGEOUS!!!

[Fiebre Verde]

Thanks Tobi!
For sure Colombia is a good source of fine beryls...

[Fiebre Verde]

At first glance this Muzo specimen does not look very appealing.
Just a couple of incomplete crystals perched on a dull calcite matrix (first image).
But as we get closer, some details start to sparkle.
Actually the round-shaped emerald on the edge of the specimen is a survivor - it has a true faceting grade!
Don't know how it escaped from the standard carnage. It might have been "protected" by a larger crystal nearby.

[Fiebre Verde]

The Polveros deposit has been known from the early 90’s, but it began producing commercial quantities only in the late 90’s.
This specimen is from the early production of this locality. It's a good example of the fine calcite crystals associated to the emeralds that comes out from the La Pita district.
The last 5 images look very much similar - I just could not resist!
Host rock is black shale.

[Fiebre Verde]

What makes this specimen interesting is... a broken crystal.
Due to pressure, crystal has broken into two almost equal parts, orthogonally to the c-axis.
Following this phase, the thermochemical conditions were favorable for a recrystallization of the discontinuity surfaces.
The upper half of the crystal is contacted.

[Tobi]

For sure one of the most aesthetic "damaged" mineral specimens ever ;-)

[Fiebre Verde]

[Fiebre Verde]

Emerald and quartz nicely perched on a large calcite rhomb.
There are a few patches of non-crystallized pyrite on the black shale host rock (not featured in the images).