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View Full Version : Can you Identify this rock? Regmaglypts???



Kevinito
2013-Jun-25, 01:19 AM
Hi all:

It is 3 inches by 3 inches, non-magnetic and relatively heavy (1.7 lbs).

Are those regmaglypts on the surface?

What type of rock is this? Thoughts???

dgavin
2013-Jun-26, 12:16 AM
Don't see anything in the Thumbnails?

Kevinito
2013-Jun-26, 01:36 AM
Don't see anything in the Thumbnails?

Sorry! It has been 10 years since I have posted here. Try these two links from my Wordpress blog . . .

http://collisionofthought.wordpress.com/?attachment_id=151
http://collisionofthought.wordpress.com/?attachment_id=152

schlaugh
2013-Jun-26, 01:59 AM
FWIW the images were there earlier. Their absence might be tied to the forum technical problems of today.

Selfsim
2013-Jun-26, 07:40 AM
Hi all:

It is 3 inches by 3 inches, non-magnetic and relatively heavy (1.7 lbs).

Are those regmaglypts on the surface?

What type of rock is this? Thoughts???Ok .. I'm hooked!
I'd like to know what kind it is, too! :confused: :)

Kevinito
2013-Jun-26, 05:11 PM
Ok .. I'm hooked!
I'd like to know what kind it is, too! :confused: :)

As would I. Any thoughts - aside from chemical testing???

Swift
2013-Jun-26, 06:54 PM
I don't know, but I have a couple of questions that might help.

Where did you find these? Did you find them in "the wild" or did you purchase them or get them from someone?

By my non-expert look, they might be meteorites with regmaglypts. But I also wonder if they are some sort of solidified lava with gas bubbles, or some sort of man-made slag.

dgavin
2013-Jun-26, 07:07 PM
Swift beat me too it.

My fist suspect is that they are rocky (as opposed to glassy) obsidian or basalt that was blasted out of a volcano. If any of the edges are very sharp, it's likely obsidian in some form.

I have see a rocks like this where basalt from the sea floor is washed up as glossy black rock with regmaglypts like impressions. Typiclay those will have a few streaks of white fossilized sea shell's inside them, some of them visable on the surface. It's very common to find these on the Oregon and Wash. coasts. The impressions are cause by errorsion of water. The most common place to find these types of shiny black rocks with sometime optional fossils are around the "Devils Punchbowl" and "Beverly Beach" region in Oregon. I used to have one I found that was about 8 inches around, and had about 20 embedded sea shells.

If you found these in the wild, a location would be helpful in narrowing down the type of material, as Swift indicated.

Kevinito
2013-Jun-27, 07:20 PM
I don't know, but I have a couple of questions that might help.

Where did you find these? Did you find them in "the wild" or did you purchase them or get them from someone?

By my non-expert look, they might be meteorites with regmaglypts. But I also wonder if they are some sort of solidified lava with gas bubbles, or some sort of man-made slag.

Thanks for the feedback! These were from the wild left to us from a grandparent. These were found quite a while ago...

Kevinito
2013-Jun-27, 07:22 PM
Swift beat me too it.

My fist suspect is that they are rocky (as opposed to glassy) obsidian or basalt that was blasted out of a volcano. If any of the edges are very sharp, it's likely obsidian in some form.

I have see a rocks like this where basalt from the sea floor is washed up as glossy black rock with regmaglypts like impressions. Typiclay those will have a few streaks of white fossilized sea shell's inside them, some of them visable on the surface. It's very common to find these on the Oregon and Wash. coasts. The impressions are cause by errorsion of water. The most common place to find these types of shiny black rocks with sometime optional fossils are around the "Devils Punchbowl" and "Beverly Beach" region in Oregon. I used to have one I found that was about 8 inches around, and had about 20 embedded sea shells.

If you found these in the wild, a location would be helpful in narrowing down the type of material, as Swift indicated.

Hey!

Thanks for the information! There are no white fossilized streaks at all and no indication of fossils. None of the edges are sharp either. This was found by a grandparent around 80 years ago in North Central Florida.

schlaugh
2013-Jun-27, 08:05 PM
From the very cool Arizona State University (http://meteorites.asu.edu/) site on meteorites:

You can also take this quiz:



Is the specimen black or brown and smooth, with no holes or bubbles on the surface?
Is the specimen solid and compact?
Is the specimen heavy compared to a "normal" rock of the same size?
Does a magnet stick to the surface of the specimen?
Is the specimen entirely made of metal, or does it show metallic specks on all parts of a broken, cut, or polished surface?

If you answered "no" to any of these questions, you probably don't have a meteorite…
Because your specimen does not have the most common characteristics of a meteorite, it is likely a terrestrial rock. Terrestrial rocks that are mistaken for meteorites are called "meteorwrongs".



ETA: North Central Florida is pretty big - can you narrow it down? Gainesville? Orlando? Ocala? Was there any industry nearby that might produce slag or other manufacturing byproducts?

schlaugh
2013-Jun-27, 08:11 PM
And apparently a researcher at the University of North Texas may (repeat: MAY) help you determine if your rock was once in space:

http://astronomy.unt.edu/meteorites.html

Kevinito
2013-Jun-28, 01:24 AM
From the very cool Arizona State University (http://meteorites.asu.edu/) site on meteorites:


ETA: North Central Florida is pretty big - can you narrow it down? Gainesville? Orlando? Ocala? Was there any industry nearby that might produce slag or other manufacturing byproducts?

From Ocala - no industry there.

1. Black and smooth with Regmaglypts.
2. Both solid and compact.
3. Yes, much heavier than a rock the same size.
4. Non-magnetic.
5. No flecks or specks of shiny metal on the surface.

Thanks!

Kevinito
2013-Jun-28, 01:28 AM
And apparently a researcher at the University of North Texas may (repeat: MAY) help you determine if your rock was once in space:

http://astronomy.unt.edu/meteorites.html

Just shot an email. I will let you know if I find anything...

Thanks!

Romanus
2013-Jul-03, 02:45 AM
Q: Will it set off a metal detector?

My op: It looks like a heavily weathered iron to me, full stop, and the weight you mention give further evidence that it's metallic. Your next step--barring something non-invasive like a metal detector--would be to try to slice off a piece and look for a shiny interior, though I can understand your reluctance with an heirloom.

Best of luck with its confirmation! It might even show meteoriticists something new.

Kevinito
2013-Jul-03, 11:51 AM
Q: Will it set off a metal detector?

My op: It looks like a heavily weathered iron to me, full stop, and the weight you mention give further evidence that it's metallic. Your next step--barring something non-invasive like a metal detector--would be to try to slice off a piece and look for a shiny interior, though I can understand your reluctance with an heirloom.

Best of luck with its confirmation! It might even show meteoriticists something new.

Good point; however, it is definitely non-magnetic. I would think that weathered iron is...

Romanus
2013-Jul-04, 07:01 PM
Having done a little more reading, it seems that if a magnet won't adhere to it, the chances of its being a meteorite are very low; even stones typically have enough metal in them for attraction.

Kevinito
2013-Jul-06, 12:16 AM
Having done a little more reading, it seems that if a magnet won't adhere to it, the chances of its being a meteorite are very low; even stones typically have enough metal in them for attraction.

Achondrites, lunar meteorites and martian meteorites do not attract magnets at all; although, my specimen does not closely resemble them. I am really curious as to what the heck it is.

dgavin
2013-Jul-06, 12:46 AM
See if it will trigger a Geiger counter, you might have a hold of something called pitchblende, which is a form of uranium ore. I just remembered that my father found a very similar looking rock when he worked for the BLM, and it would trigger a Geiger counter.

Kevinito
2013-Jul-06, 01:02 AM
OK,

I filed a small portion of the rock and it revealed flecks of shiny metal (looks like silver at varying angles). I also discovered it is mildly magnetic...

What the heck does this mean???

Kevinito
2013-Jul-06, 01:03 AM
See if it will trigger a Geiger counter, you might have a hold of something called pitchblende, which is a form of uranium ore. I just remembered that my father found a very similar looking rock when he worked for the BLM, and it would trigger a Geiger counter.

Fascinating! I checked online and many of the pitchblende samples have bubbles protruding outward - all these "bubble" formations are inverted...Thanks!

dgavin
2013-Jul-07, 05:52 PM
Well if it's metallic, and slightly magnetic, there is a chance it might be a meteorite. Try taking it to a local university that has an astronomy, or an earth and planetary sciences program. Don't sell it to them though:D

Selfsim
2013-Jul-17, 10:53 PM
Tektite ... ? (http://en.wikipedia.org/wiki/Tektite)
A type of fused silica glass formed from hot ejecta following impacts ... (my guess) ..

PS: Just acquired such a sample myself ... its quite heavy .. and doesn't look anything like glass, either .. very black and pitted ...

ShinAce
2013-Jul-18, 02:24 PM
I'm trying to remember my earth sciences course!

You could measure its weight and then record its displacement(http://en.wikipedia.org/wiki/Archimedes'_principle) to get its density.

We know it's black/red, and magnetic. Freshly cut it is metallic. Great. Very high chance of iron/hematite.

Other good things to know are:
-streak(http://meteorites.wustl.edu/id/streak.htm)
-hardness
-cleavage(unlikely from what I've seen)

Also see:
http://kk.org/cooltools/archives/5799

My guess is weathered hematite:
http://www.gemsandjewels.net/hematite-27.htm

edit: if the streak is red, you've got hematite. http://meteorite-identification.com/streak.html

Selfsim
2013-Jul-18, 09:06 PM
Tektite can also have iron inclusions.

Could the 'flecks of shiny metal' be mistaken for flecks of shiny glass?

beyond light
2013-Jul-19, 07:38 AM
they're "meteo-sats" from outer-space, what do i know...