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Unique Colombian emerald inclusions
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Author:  Gustavo [ Sun Sep 26, 2010 2:20 pm ]
Post subject:  Unique Colombian emerald inclusions

I found two crystals in a parcel with very rare inclusions. They look as though they have been faceted using the micro concave method.

I wanted to share them with you as I have never seen anything like this during my years working with emeralds. I have asked many dealers and they have never seen inclusions like this before. A true collectors piece.

Attachments:
Unique inclusions.jpg
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Unique emerald inclusions..jpg
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Author:  maialetto [ Sun Sep 26, 2010 2:46 pm ]
Post subject:  Re: Unique Colombian emerald inclusions

It really looks like one I found in a topaz crystal... :?:
Image

Author:  flameswithin [ Sun Sep 26, 2010 10:38 pm ]
Post subject:  Re: Unique Colombian emerald inclusions

This is one of those times I wish I was a scientist and could posit a theory on how such an inclusion might occur! Seriously cool looking, though!

Author:  maialetto [ Mon Sep 27, 2010 3:26 am ]
Post subject:  Re: Unique Colombian emerald inclusions

What freaks me out is that a similar (at first sight...) and peculiar feature is occurring in two different minerals with very different symmetry... Any feature at the top (pinacoid) of the crystals? Like a double spiral made of little steps?
Something similar to this (look at the picture on the right, it's more clear):
Image
Only at a different scale and exagonal... :mrgreen:

Author:  Duncan Miller [ Mon Sep 27, 2010 3:42 am ]
Post subject:  Re: Unique Colombian emerald inclusions

These helical inclusions also occur in aquamarine. Some time ago John White posted a picture of one in a cut stone on Jorde Fabre's FMF forum, and then I found one in my collection of rough. As far as I know, no-one has come up with an explanation of these helical growth features. My example does not have a core of foreign material. I analysed the cut-off end using EDS in a SEM and it showed nothing but beryl. The growth feature consists of a helical crack, with an even pitch, and regularly spaced wing-liked, paddle-shaped 'extensions'. it is really interesting to see the example in topaz.

Duncan

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Helical feature in aquamarine.jpg
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Author:  maialetto [ Mon Sep 27, 2010 4:29 am ]
Post subject:  Re: Unique Colombian emerald inclusions

In my opinion the process it's probably driven by the xtl growth mechanism, in this case EDS wouldn't give many answers. The SEM images you took were on the "natural" top of the xtl or it was a polished surface? Any "hole" with a peculiar shape and/or steps close to the axis of the feature? :)

Author:  Faceting 101 by Arya [ Mon Sep 27, 2010 11:56 am ]
Post subject:  Re: Unique Colombian emerald inclusions

That is by far the single coolest emerald I've ever seen. PLEASE DON'T CUT IT!!! :) A perfect specimen showpiece if I ever saw one.

You know...polishing the edges into a hex shape and putting it on a necklace doesn't sound bad either...but that would be ruining its naturalness. Then again...

Author:  mehoose [ Mon Sep 27, 2010 8:38 pm ]
Post subject:  Re: Unique Colombian emerald inclusions

I'm gonna swear. Bloody brilliant. :P 8)

Author:  Gustavo [ Mon Sep 27, 2010 10:06 pm ]
Post subject:  Re: Unique Colombian emerald inclusions

I am amazed to learn that the same inclusions occurs in topaz and aquamarine. Thanks for the photos they are great.

I am not going to cut any of this stones but they could be worn as they are as pendants. None of the sides of the stones have been polished to my knowledge.

Many thanks.

Author:  Proteus [ Tue Sep 28, 2010 12:03 am ]
Post subject:  Re: Unique Colombian emerald inclusions

I have proof that it can occur in spodumene as well.

This is a photomicrograph of this same type of inclusion in a triphane that I cut a couple years ago.

It's much smaller, the shot is at around 60x magnification. I always jokingly called it a rotini noodle inclusion.

Attachments:
Triphanenoodle.jpg
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Author:  allen [ Tue Sep 28, 2010 1:00 am ]
Post subject:  Re: Unique Colombian emerald inclusions

Funny that such a distinctive inclusion in so many different minerals is largely unexplained.

Author:  Gearloose [ Tue Sep 28, 2010 8:05 am ]
Post subject:  Re: Unique Colombian emerald inclusions

If all these mineral crystals are hydrothermal, and the gas pressures are at equilbrium, maybe a bubble was excluded from the crytallizing lattice, resided for a while, then again excluded, rose, sat there, etc.

Just a wild desperate guess. If the liquid is saturated with gas, there is no reason for the bubble to be dissolved, or have anywhere else to go.

Author:  Gustavo [ Tue Sep 28, 2010 9:13 am ]
Post subject:  Re: Unique Colombian emerald inclusions

Jon I agree with you,

I though perhaps it was water rushing through the crystal as it was forming, hence the swirling type of inclusion left.
:?:

Author:  Gearloose [ Tue Sep 28, 2010 9:18 am ]
Post subject:  Re: Unique Colombian emerald inclusions

Quote:
I though perhaps it was water rushing through the crystal as it was forming, hence the swirling type of inclusion left.

Looks like ithe bubble was stopping, sitting, and starting. Note that in the spodumene, the zigzag effect may coincide with cleavage planes. The crystal tried to grow perfectly but is disrupted by the inclusion.

Author:  gsellis [ Tue Sep 28, 2010 12:39 pm ]
Post subject:  Re: Unique Colombian emerald inclusions

It is the Tunneling Neutrino Beetle. It feeds on Be and other periodic metals. :^o

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