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The information provided within this Forum about localities is only given to allow reference to them. Any visit to any of the localities requires you to obtain full permission and relevant information prior to your visit. FMF is strictly against any illicit activities related to collecting minerals.
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| Search found 91 matches |
| Author | Message |
|---|---|
 Topic: Trying to find information on rose/pink quartz and tourmaline associations. |
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| Amir Akhavan Replies: 17 Views: 2151 |
 Forum: Minerals and Mineralogy Posted: Mar 30, 2024 09:14 Subject: Re: Trying to find information on rose/pink quartz and tourmaline associations. |
| I see no reason to doubt these are natural, but the gemlab tests are meaningless with respect to the identity of the material.
Two diagnostic features of pink quartz are UV and heat sensitivity (ros ... |
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| Topic: Amethyst |
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| Amir Akhavan Replies: 17 Views: 8718 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: Feb 25, 2023 13:51 Subject: Re: Amethyst |
| I agree with Jordi, could also be from Bolivia. | |
| Topic: Amethyst |
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| Amir Akhavan Replies: 17 Views: 8718 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: Feb 25, 2023 13:49 Subject: Re: Amethyst |
| Sideways and from the back, please. So far it looks natural and not assembled, as I first thought.
A hardness test is not necessary, but it doesn't hurt, of course, This cannot be fluorite, beca ... |
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| Topic: Amethyst |
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| Amir Akhavan Replies: 17 Views: 8718 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: Feb 25, 2023 12:23 Subject: Re: Amethyst |
| Without doubt amethyst, yes, but I wonder if they have been assembled or not.
The crystals are probably from Brejinho das Ametistas in Bahia, Brazil, the "corroded prism and lower edges of the r ... |
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| Topic: Amethyst |
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| Amir Akhavan Replies: 17 Views: 8718 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: Feb 25, 2023 11:31 Subject: Re: Amethyst |
| This looks odd.
What does it look from the side and below? |
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| Topic: Galena Spinel law |
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| Amir Akhavan Replies: 8 Views: 5649 |
Forum: Minerals and Mineralogy Posted: Feb 12, 2023 18:10 Subject: Re: Galena Spinel law |
| Crystal faces that belong to different forms often differ in their surface features, like luster, growth hillocks, steps, dents or other patterns.
These features vary a lot between different specime ... |
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| Topic: Semi-spherical exterior, radiating interior stone |
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| Amir Akhavan Replies: 31 Views: 12627 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: Feb 12, 2023 06:28 Subject: Re: Semi-spherical exterior, radiating interior stone |
| Sorry, I've sent you an alamy linkin German, not English.
Here it is: http://www.alamy.com/stock-photo-iron-pyrite-nodule-or-concretion-fes2-from-beach-at-east-wear-bay-113378446.html?imageid=AC80D4 ... |
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| Topic: Semi-spherical exterior, radiating interior stone |
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| Amir Akhavan Replies: 31 Views: 12627 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: Feb 11, 2023 06:31 Subject: Re: Semi-spherical exterior, radiating interior stone |
| https://www.mineralienatlas.de/VIEWmaxFULL.php/param/1500751758-Pyrit-strahlig-Pyrite.jpg
https://www.mineralienatlas.de/VIEWmaxFULL.php/param/1500751680-Pyrit-strahlig-in-Kalkstein-Pyrite.jpg h ... |
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| Topic: Can alpha radiation from titanite, zircon, etc. affect other mineral specimens? |
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| Amir Akhavan Replies: 4 Views: 3667 |
Forum: Minerals and Mineralogy Posted: Feb 10, 2023 19:05 Subject: Re: Can alpha radiation from titanite, zircon, etc. affect other mineral specimens? |
| As the others have said, yes, alteration takes place, but this will take forever.
But there is also another aspect: Minerals get metamict not only because of self-inflicted radiation damage. The ... |
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| Topic: Semi-spherical exterior, radiating interior stone |
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| Amir Akhavan Replies: 31 Views: 12627 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: Feb 10, 2023 18:54 Subject: Re: Semi-spherical exterior, radiating interior stone |
| I agree with those who say very likely limonit(ized) concretion.
I used to find many pyrite (often called marcasite) concretions in a limestone quarry that looked like these. Interestingly they had ... |
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| Topic: Tucson Shows 2023 - let the fun begin |
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| Amir Akhavan Replies: 77 Views: 50721 |
Forum: News about Shows Posted: Jan 26, 2023 13:53 Subject: Re: Tucson Shows 2023 - let the fun begin |
| I'm surprised fluorite fake loops are still sold.
https://www.mindat.org/mesg-563562.html |
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| Topic: Spherical inclusions in amethyst - cristobalite? vs fluorite |
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| Amir Akhavan Replies: 15 Views: 8823 |
Forum: Minerals and Mineralogy Posted: Jun 30, 2022 14:06 Subject: Re: Spherical inclusions in amethyst - cristobalite? vs fluorite |
| One of the tasks at Saint Marie aux Mines ( apart from catching covid in the badly ventilated crowded halls ) was finding more samples.
All I had to do was to look for unpolished amethyst tips at *a ... |
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| Topic: In memoriam - Eloïsa Artola (Elo) |
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| Amir Akhavan Replies: 5 Views: 9883 |
Forum: In Memoriam Posted: Jun 15, 2022 12:54 Subject: Re: In memoriam - Eloïsa Artola (Elo) |
| I'm sad to read this. Eloïsa had something. I immediately liked her, you could feel she was a "good soul" in the best sense of the word.
My condolences to Joaquim and the family. |
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| Topic: Es -Semara Chalcedony |
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| Amir Akhavan Replies: 4 Views: 3894 |
Forum: Minerals and Mineralogy Posted: May 25, 2022 14:08 Subject: Re: Es -Semara Chalcedony |
| Hi Jordi,
thanks for the response! I have to try harder at Sainte Marie to find one with traces of fossils in them. :-) It's odd that there is so little information on specimens like these tha ... |
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| Topic: Es -Semara Chalcedony |
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| Amir Akhavan Replies: 4 Views: 3894 |
Forum: Minerals and Mineralogy Posted: May 25, 2022 07:12 Subject: Re: Es -Semara Chalcedony |
| A photo of a specimen cut in half. The central part was used to prepare a thin section.
The section on the photo is still 2.1mm thick and 32mm wide, and was reduced to 30µm (no photo of that yet). ... |
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| Topic: Es -Semara Chalcedony |
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| Amir Akhavan Replies: 4 Views: 3894 |
Forum: Minerals and Mineralogy Posted: May 24, 2022 20:11 Subject: Es -Semara Chalcedony |
| Hi,
Jordi and many other dealers offer these odd looking brown chalcedony nodules from Smara/Es Semara in Morocco. Sometimes you read that they are silicified sponges. @ Jordi: Is there any eviden ... |
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| Topic: What is it? |
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| Amir Akhavan Replies: 6 Views: 3755 |
Forum: FOR BEGINNERS: What is it? Where is it from? Posted: May 13, 2022 10:19 Subject: Re: What is it? |
| Curvelo, Minas Gerais, Brazil.
https://www.mindat.org/gallery.php?loc=105902&min=3337 |
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| Topic: Is this a ruby? |
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| Amir Akhavan Replies: 12 Views: 5422 |
Forum: What is it? - Where is it from? Posted: May 10, 2022 08:06 Subject: Re: Is this a ruby? |
| Again and again, the sensory thing in definitions...
When I studied biology, I took a course in psychophysics at the Max Planck Institute of Biocybernetics. The professor at one lab studied color p ... |
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| Topic: wisdom quartz |
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| Amir Akhavan Replies: 6 Views: 4193 |
Forum: What is it? - Where is it from? Posted: Apr 16, 2022 18:43 Subject: Re: wisdom quartz |
| As Alfredo and Bob have mentioned, these are amethyst specimen from South Africa, more specifically, from here:
https://www.mindat.org/loc-204011.html Cactus quartz and spirit quartz are terms for ... |
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| Topic: What is the correct name for this rock? |
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| Amir Akhavan Replies: 6 Views: 9412 |
Forum: What is it? - Where is it from? Posted: Mar 30, 2022 08:10 Subject: Re: What is the correct name for this rock? |
| Obsidian with narrow bands of intense devitrification. The small dots are spots where the glass devitrified ("de-glassed", crystallized). | |
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