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Here's a totally fascinating development. I have a couple pieces that in my last pdf I said were good candidates for having chains of sand grains, based on their overall shapes. I ground a flat on e ...

In the images above, there's a whitish knob on the bottom of the piece, apparently quartz. I cut that off and polished it. The glass has lots of inclusions, so the fossil is still hard to see. So I ...

Found another fossil. This is the first piece of LDG that I bought specifically because it looked like a fossil. When I bought it I thought it might be a bug or a plant part. The object was highly ...

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 ...

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 ...

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 ...

Here's just the cavity.

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

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 ...

Author	Message
Topic: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jun 10, 2025 21:28 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Here's a totally fascinating development. I have a couple pieces that in my last pdf I said were good candidates for having chains of sand grains, based on their overall shapes. I ground a flat on e ...
Topic: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jun 10, 2025 19:20 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	In the images above, there's a whitish knob on the bottom of the piece, apparently quartz. I cut that off and polished it. The glass has lots of inclusions, so the fossil is still hard to see. So I ...
Topic: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jun 03, 2025 14:44 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Found another fossil. This is the first piece of LDG that I bought specifically because it looked like a fossil. When I bought it I thought it might be a bug or a plant part. The object was highly ...
Topic: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Apr 29, 2025 11:50 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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 ...
Topic: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Apr 19, 2025 04:10 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Apr 12, 2025 11:48 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Apr 11, 2025 03:23 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Here's just the cavity.
Topic: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Apr 10, 2025 16:44 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Mar 19, 2025 11:57 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Mar 14, 2025 12:47 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jan 14, 2025 10:48 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jan 13, 2025 15:52 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jan 13, 2025 15:09 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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 ...
Topic: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jan 12, 2025 13:10 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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
Craig Hagstrom Replies: 45 Views: 88868	Forum: Minerals and Mineralogy Posted: Jan 12, 2025 11:09 Subject: Re: Libyan Desert Glass Structure
Craig Hagstrom Replies: 45 Views: 88868	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 ...