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Possible Man Made Geodes (listed as HEULANDITE GEODE)

Posted by Al User  
Al User January 07, 2019 09:18PM
I have seen some of these geodes coming out of India. They look odd like their walls are made from concrete? Maybe its just because they are smoothing the material it was cut from? But it set off a red flag wanted the professional opinion.


This is from another listing but something I have seen before

Reiner Mielke January 07, 2019 09:22PM
I don't see anything odd about them other than calling them geodes. Grinding the matrix around a pocket off does not a geode make. However it does make for a much lighter in weight specimen.
Al User January 07, 2019 09:24PM

And another one
Doug Daniels January 07, 2019 09:26PM
If those were man-made, someone had way too much time on his hands. And, I don't see how it could have been done. The matrix looks like good ol' basalt, but ground down to reduce the amount. I'd say natural.
Al User January 07, 2019 09:28PM
Thank you Reiner for the insight. Good to know they are man made.

Yea I think using the geode terminology scared me since they are not really geodes. Just pocket rock specimens :)
Al User January 07, 2019 09:29PM
Thank you as well Doug!
Hiro Inukai January 07, 2019 10:43PM
Many of the zeolite specimens coming from India are prepared in this way, whenever the growth occurs in a vug or pocket. The purpose of cutting and shaping the matrix in this way is to make them more aesthetically pleasing, highlighting the way the crystals grew in the pocket. They are not true geodes, but unless otherwise altered, the crystals themselves are natural and their occurrence in the pocket is also natural.

That said, they are frequently marketed or described as "geodes," partly because the layperson is only familiar with the use of the term in the colloquial sense, rather than a strict geological sense, and partly because it sounds more appealing. I disagree with this usage as I do with all scientific terms that are used improperly or imprecisely, but even I am guilty of calling a strawberry a fruit, or a tomato a vegetable.

I would say that most mineral collectors can tell that the matrix has been shaped using a saw; the marks are unmistakable. But as to whether this is considered "artificial" or not is subjective; after all, many specimens can only be collected by sawing them off, and ultimately, what is the difference between sawing and chiseling off?

I bought a small and cheap example of this kind of Indian zeolite, but not with such obvious saw marks. One of the nice things about these is that they do tend to be well-protected from contacting, so very delicate formations remain pristine.
Bob Harman January 07, 2019 10:50PM
From the point of view in this thread, the Indian zeolite "geodes" are similar to the Brazilian and Uruguayan amethyst "geode" or "cathedral" specimens. Crystal lined cavities in basalt lava flows, worked out of the basalt, and "cut" down to reduce weight and facilitate handling. As HIRO notes, it is up to the buyers as to whether they are comfortable with their type of preparations. CHEERS.....BOB
Scott Rider January 07, 2019 11:14PM
I know some may shun trimming specimens in the way that the Indian miners seem to use. I personally have no qualms with the use of this as long as they do it well. I've seen some that are smooth and well prepared, and some that are jagged and not really that aesthetic. I think its better than having a 20 pound hunk of basalt for a small cavity of crystals however. I'd rather they trim it down to a more manageable weight as it can save money in shipping these the specimens and make it easier to display them as well.
Al User January 07, 2019 11:29PM
Thank you Hiro/Bob/Scott for the insight about these specimens.

I agree with you Scott that it makes sense to me to have these specimens cleanly cut so they are actually manageable.
Scott Rider January 07, 2019 11:35PM
Indeed, it just makes things easier for everyone!! Plus its really hard to sell a small cluster or single crystal that is attached to a huge matrix, its harder to sell, transport and to display!!

As a field collector myself, I have found some really good specimens that were attached to large rocks. Once home, I was able to assess the specimen and trim them down. Had I not done that I probably couldn't have sold them, or at least sold them for what I wanted... One example was a smoky quartz cluster that was attached to a 25 pound hunk of granite. Trimmed that sucker down to 5 pounds,!!! But that was a pretty extreme example.

Edited 1 time(s). Last edit at 01/07/2019 11:36PM by Scott Rider.
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