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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 16 matches |
| Author | Message |
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 Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
 Forum: Minerals and Mineralogy Posted: Apr 29, 2025 11:50 Subject: Re: Libyan Desert Glass Structure |
| I've uploaded a new release of my report. This includes 3D images of the two specimens with significant voids - one with apparent seeds, one with the insect nest.
Had an epiphany with my morning c ... |
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| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Apr 19, 2025 04:10 Subject: Re: Libyan Desert Glass Structure |
| I uploaded a model of the entire rock, same link as above. I stitched the cavity model into place in a model of the rock, both done with photogrammetry. Pretty pleased with the fidelity, but it does ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Apr 12, 2025 11:48 Subject: Re: Libyan Desert Glass Structure |
| I put a preliminary copy in STL format on Thingiverse, if anyone wants to mess with it. You can print a model of it, but you'll have to set that up. The model as is has no thickness and is not manif ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Apr 11, 2025 03:23 Subject: Re: Libyan Desert Glass Structure |
| Here's just the cavity. | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Apr 10, 2025 16:44 Subject: Re: Libyan Desert Glass Structure |
| Here's something fascinating. I wanted to do a better image of the cavities in my LDG_11 sample. It has what appears to be a seed cast with several leaf tips at its mouth, and this cast is visible b ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Mar 19, 2025 11:57 Subject: Re: Libyan Desert Glass Structure |
| Sorry, I just accidentally deleted someone's post here. If it was yours, please re-post it. The post appeared double on my screen, so I wanted to remove the duplicate, but they both disappeared. Must ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Mar 14, 2025 12:47 Subject: Re: Libyan Desert Glass Structure |
| Uploaded a new version. This has some improved images - getting better with that microscope. I laid out three evidentiary tests for my thesis, and added some graphic aids. The coolest addition is a ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Jan 14, 2025 10:48 Subject: Re: Libyan Desert Glass Structure |
| Worms are surface structures on which chemical dissolution is concentrated. They are produced by filamentous microbial colonies (bacteria and fungi) present within the soil that have the ability to cr ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Jan 13, 2025 15:52 Subject: Re: Libyan Desert Glass Structure |
| It's not really a crystal structure, just the way glass etches. If you take a piece of beer bottle glass - pure glass with no crystals in it - and drip diluted hydrofluoric acid (very dangerous!) over ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Jan 13, 2025 15:09 Subject: Re: Libyan Desert Glass Structure |
| Marco, thank you for the thoughtful response.
Regarding the erosion grooves, I have no expertise in the area. But consider the image below with curved striations. This is a closeup of one I showe ... |
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| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Jan 12, 2025 13:10 Subject: Re: Libyan Desert Glass Structure |
| Here's a couple samples. I don't know what these lines mean. My conjecture is that they're crystals formed from threads of sand grains as laid down. The first is a closeup about 8 mm wide, showing ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Jan 12, 2025 11:09 Subject: Re: Libyan Desert Glass Structure |
| Nowhere do you indicate or hint why you or anyone would be led to think there are "hidden" small linear crystals. LDG is a glass. Glasses don't have crystals by definition.
I indicate it ... |
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| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Jan 11, 2025 20:02 Subject: Re: Libyan Desert Glass Structure |
| Observing a thin section with transmitted polarized light under a petrographic microscope will quickly indicate whether there are long chains of crystals present or whether it's mostly just glass, as ... | |
| Topic: Libyan Desert Glass Structure |
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| Craig Hagstrom Replies: 42 Views: 13562 |
Forum: Minerals and Mineralogy Posted: Jan 11, 2025 11:01 Subject: Libyan Desert Glass Structure |
| Libyan Desert Glass is often said to have no crystals, but it actually has many. Samples frequently have what appear to be threadlike crystals revealed through weathering. For any one piece these ar ... | |
| Topic: Presentation of new members - Reference Thread |
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| Craig Hagstrom Replies: 528 Views: 2700596 |
Forum: Off-Topic and Introductions Posted: Jan 10, 2025 18:24 Subject: Re: Presentation of new members - Craig Hagstrom, interested in Libyan desert glass |
| Welcome to FMF Mr Hagstrom.
Ready to share with us your fist-size Lake Superior agate picked up in your driveway about 70 years ago? It’s always nice to be able to show some of our first pieces. ... |
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