Geology, Geodes, Fossils & Meteorites

[SusanLR]

Nice tourmaline speciman. 9 inches long.

 

[Mia]

Saltwater, Mantanzas province, Cuba. 2016

 

[Mary Terry]

View attachment 51488 Nice tourmaline speciman. 9 inches long.

That's a nice specimen. Tourmaline was the favored gemstone of the Maya. I bought a tourmaline ring in Mexico last month which is a peach color in sunlight but green in artificial light.

 

[Mary Terry]

Here are photos of the rock I think may be a meteorite. Does anyone have an opinion?

 

[Shamar]

Here are photos of the rock I think may be a meteorite. Does anyone have an opinion?


View attachment 51493 View attachment 51499

It doesn't really look like a meteorite, to me it looks like the interior of a concretion. They frequently have very high iron concentrations and can be surprisingly dense. The slight magnetism may be due to magnetite (Fe3O4) on the surface..

On a meteorite, the black fusion crust is usually the first thing to weather off, the interior then slowly weathers to iron oxide. Your specimen appears unweathered on the exterior and oxide (hematite, Fe2O3, or limonite FeO(OH)-nH2O) on the interior.

I probably sounded like Isaac on the Orville with that, but I tend to use very precise and technical language when doing an analysis. Just the way I am.

 

[Shamar]

People have been posting interesting geology photos, so I thought I would join in. This is a polished cross section from the Allende meteorite.

Allende fell Feb 08, 1969 near Allende, Chihuahua, Mexico. Over two tons of material were found and extensively studied. It is classed as a carbonaceous chondrite, due to the chondrules in the interior. These are the round particles, which are primordial interstellar dust. These chondrules are actually older than the age of the Earth. It is considered one of the best preserved carbonaceous chondrites.

 

[SusanLR]

These are tektite droplets from the meteor crater in Arizona.
Called Apache Tears locally, there was a large debris field of them from that meteorite.

 

[Ken S.]

I have the Geology Photo Album made and ready for everyone to post media on. There are a few of my Cherts posted so far. Have many more photos to take and upload still.

 

[Mary Terry]

It doesn't really look like a meteorite, to me it looks like the interior of a concretion. They frequently have very high iron concentrations and can be surprisingly dense. The slight magnetism may be due to magnetite (Fe3O4) on the surface..

On a meteorite, the black fusion crust is usually the first thing to weather off, the interior then slowly weathers to iron oxide. Your specimen appears unweathered on the exterior and oxide (hematite, Fe2O3, or limonite FeO(OH)-nH2O) on the interior.

I probably sounded like Isaac on the Orville with that, but I tend to use very precise and technical language when doing an analysis. Just the way I am.

That makes sense. I'm going to keep it with my collection as I have had it for about 40 years. Thank you for the info. I had to google Isaac on the Orville to figure out that that meant. Geologists - all scientists - should use very precise and technical language and I appreciate it.

 

[Mary Terry]

These are tektite droplets from the meteor crater in Arizona.
Called Apache Tears locally, there was a large debris field of them from that meteorite.
View attachment 51595 View attachment 51596

That looks a lot like my specimen. I actually hiked down to the bottom of the crater (the one near Flagstaff) back in the 1970s. The Park Service doesn't allow people to do that anymore so I'm glad I had a chance to do it.

 

[Mary Terry]

I have the Geology Photo Album made and ready for everyone to post media on. There are a few of my Cherts posted so far. Have many more photos to take and upload still.

Nice! I'm not sure what the big birds and conversion tables mean. LOL

I'm going to start photo'ing some of my collection and post them, too. My husband showed me how to do that the other day.

 

[Shamar]

I have the Geology Photo Album made and ready for everyone to post media on. There are a few of my Cherts posted so far. Have many more photos to take and upload still.

How, specifically, do I access this to view or upload? A search of "geology" in the media area turns up no results.

Never Mind, I figured it out.

 

[tducey]

Not something that has interested me but still a good topic for those who may be interested. Thanks for sharing your interest.

 

[Ken S.]

I finally got all my rocks & such posted. Hoping to see others from other locations.

 

[Butterfly88]

I have a small rock and mineral collection. My largest specimen is calcite on smokey quartz that's valued over $100. I won it as a door prize at a rock and mineral show.

 

[Mary Terry]

I finally got all my rocks & such posted. Hoping to see others from other locations.

You have some really nice specimens. I'm going to photograph some of my collection, too.