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Welcome!
Tektites with Brown
Posted by Gordon c De'young
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Re: Tektites with Brown August 27, 2009 03:54PM |
Registered: 3 years ago Posts: 46 |
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Re: Tektites with Brown August 27, 2009 05:02PM |
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Registered: 5 years ago Posts: 326 |
Gordon:
Please keep us posted as your inquiry into these objects progresses; this has been an interesting thread to follow. Personally, I am betting on "not tektites", although I have seen a bunch of similar looking objects offered for sale as tektites.
You may want to check up on some of the Mindat posters - these folks really know what they are talking about and are the "experts". Just so you know, there are some big time museum professionals lurking in the background on Mindat. Perhaps some of them will chime in on the debate.
Mark
Please keep us posted as your inquiry into these objects progresses; this has been an interesting thread to follow. Personally, I am betting on "not tektites", although I have seen a bunch of similar looking objects offered for sale as tektites.
You may want to check up on some of the Mindat posters - these folks really know what they are talking about and are the "experts". Just so you know, there are some big time museum professionals lurking in the background on Mindat. Perhaps some of them will chime in on the debate.
Mark
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Re: Tektites with Brown August 27, 2009 06:51PM |
Registered: 5 years ago Posts: 25 |
This is a great topic!! Dr. Kring explained to me how to find tecktites!!! simply put,.. like this,..tecktites are simular to obsidian,and if you find a tecktite,..go up hill from where you found the first tecktite, and it can lead you to more,although I seem to be a magnet for them,..I find that they are around New Mexico in great numbers. also, in Arizona. but, this should be the case! nevertheless,it can lead you to a meteorite as well, with the right eye...they can be found.tecktites are more dull, not as shiny as obsidian.and testing can be a great way to further your knowlege!! most tecktites are hundreds and thousands of yrs. old.
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Re: Tektites with Brown August 28, 2009 05:30PM |
Registered: 3 years ago Posts: 46 |
Dear Gordon: Boy, am I embarassed! I am so sorry that we at the Smithsonian have let you down so badly. The basic problem is that our department (in the Museum of Natural History) has no person familiar with tectiites. A couple of our meteorite specialists looked at the sample and said, "It sure looks like a tectite," but none of these people could definitely say, Yes, it is one." They mentioned the name of a specalist (at some other institution) who could examine it, and one of our staff even said she'd send it to him. I, mistakenly, thought she had done that and that everything was in order. But it obviously was not. I'm living in Seattle for the summer, so it's hard for me to deal with this issue right now. But I'll be returning to the Smithsonian on September 7th, and I could try to get things back on track soon after that. In particular, I could send your sample to that specialist, and you could soon have a definite answer. Is that OK with you? Regards and regrets, Dick Fiske P.S. Please tell Harry Smedes that I'm not a bad guy--- just a sometimes disorganized guy! i just received this message a little while ago strang he mis spells(lol) Well we still have Drw Weller, at Cochise college in Arizona.And hes a very busy guy he leads up the geology dept.and has explained he hasto create two new classes fore this year as well as his other duties.I am will to send samples(dirty ones) to anyone all they need to do is ask.In return i ask that if any testing is done i would like to have copies of the results.
Edited 1 time(s). Last edit at 08/28/2009 05:37PM by Gordon c De'young.
Edited 1 time(s). Last edit at 08/28/2009 05:37PM by Gordon c De'young.
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Re: Tektites with Brown September 02, 2009 03:48AM |
Registered: 3 years ago Posts: 46 |
Well i recieved this e-mail today from Dr Weller.{quote}.. Gordie,
I finally got a chance to take a closer look at the “tektites”.
I am still somewhat caught on a definitive answer.
On the plus side:
They are the correct color, overall shape, the are definitely glass, correct size range, and some have surface features similar to tektites.
On the negative side:
I broke a real tektite from the Australasian fall for comparison. It was difficult to break the Australasian tektite; it took several tries. Your tektite broke much easier. However, both appeared to be a shiny black glass. Breaking easier makes me suspect that your tektite might have a higher water content. Real tektites have an extremely low water content, while obsidians have a fairly high water content.
Next, your tektite on a thin edge of broken glass has a light gray color with just the very slightest tint of green. The reason that green is so important is that at the high temperatures at which tektites are created, oxygen is driven out and the iron present is all converted to ferrous iron, giving the tektite a strong green color. The moldavites are all an intense green. The Australasian tektites are a dark brown with a green tint; their color comes from the ferrous green plus a reddish color from submicroscopic spherules of iron that were injected into the glass when the meteorite struck the ground. Your tektite only has a bare hint of green; it resembles some obsidians. There is a hint of some layering or color variation in you tektite. I lack a gem cutter’s diamond saw to make a thin slice of the tektite to examine it thoroughly.
The avocado surface texture is different than the surface of any tektite that I have ever observed. On the other hand, some of your tektites do have surfaces very similar to those found on real tektites.
I am still caught between the two possible origins: tektites versus volcanic glass. The main feature that will determine the answer is the water content of the glass. I checked on the Internet and I have the names and address of some geologists who might be interested and who can perform the necessary tests. If you want to, you can mention my name and title as referring you to them.
S.S. Hughes, J.W. Delano, and R.A. Schmidt
Department of Chemistry and Geology
Oregon State University
Corvallis, OR 97331
I hope this helps a bit. I would love for these stones to be real tektites, because it would represent a new fall.
But I am cautious because of the large amounts of obsidian that have erupted in the Oregon area.
Sincerely,
Roger Weller
I finally got a chance to take a closer look at the “tektites”.
I am still somewhat caught on a definitive answer.
On the plus side:
They are the correct color, overall shape, the are definitely glass, correct size range, and some have surface features similar to tektites.
On the negative side:
I broke a real tektite from the Australasian fall for comparison. It was difficult to break the Australasian tektite; it took several tries. Your tektite broke much easier. However, both appeared to be a shiny black glass. Breaking easier makes me suspect that your tektite might have a higher water content. Real tektites have an extremely low water content, while obsidians have a fairly high water content.
Next, your tektite on a thin edge of broken glass has a light gray color with just the very slightest tint of green. The reason that green is so important is that at the high temperatures at which tektites are created, oxygen is driven out and the iron present is all converted to ferrous iron, giving the tektite a strong green color. The moldavites are all an intense green. The Australasian tektites are a dark brown with a green tint; their color comes from the ferrous green plus a reddish color from submicroscopic spherules of iron that were injected into the glass when the meteorite struck the ground. Your tektite only has a bare hint of green; it resembles some obsidians. There is a hint of some layering or color variation in you tektite. I lack a gem cutter’s diamond saw to make a thin slice of the tektite to examine it thoroughly.
The avocado surface texture is different than the surface of any tektite that I have ever observed. On the other hand, some of your tektites do have surfaces very similar to those found on real tektites.
I am still caught between the two possible origins: tektites versus volcanic glass. The main feature that will determine the answer is the water content of the glass. I checked on the Internet and I have the names and address of some geologists who might be interested and who can perform the necessary tests. If you want to, you can mention my name and title as referring you to them.
S.S. Hughes, J.W. Delano, and R.A. Schmidt
Department of Chemistry and Geology
Oregon State University
Corvallis, OR 97331
I hope this helps a bit. I would love for these stones to be real tektites, because it would represent a new fall.
But I am cautious because of the large amounts of obsidian that have erupted in the Oregon area.
Sincerely,
Roger Weller
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Re: Tektites with Brown October 16, 2010 12:24AM |
Registered: 2 years ago Posts: 1 |
Pardon the lateness of this addition to the topic. I assume you have received your answer by now- these samples will almost certainly be obsidian. I have samples from Healdsburg, CA, Safford, AZ, southern NV and from Peru. I have seen photos of remarkable specimens from New Mexico, Columbia and Chihuahua State in Mexico.
Most of the above varieties have been analyzed and they are obsidian. Healdsburg glass is the most troublesome one to place- like a tektite it is quite dry, has a very high fusion temp and some reduced-phase iron; but abundant microliths would be hard to explain in a tektite and Healdsburg is full of them.
I have found over 750 bediasites and one georgite and collected some obsidian(?) specimens near Healdsburg. I collect tektite analogs and I am always open to adding more specimens from different locations.
Should you recover specimens that are teardrop or dumbell shaped and they are glass then you can get excited- the likelihood of being a tektite would be very great!
Happy hunting,
Briman
Most of the above varieties have been analyzed and they are obsidian. Healdsburg glass is the most troublesome one to place- like a tektite it is quite dry, has a very high fusion temp and some reduced-phase iron; but abundant microliths would be hard to explain in a tektite and Healdsburg is full of them.
I have found over 750 bediasites and one georgite and collected some obsidian(?) specimens near Healdsburg. I collect tektite analogs and I am always open to adding more specimens from different locations.
Should you recover specimens that are teardrop or dumbell shaped and they are glass then you can get excited- the likelihood of being a tektite would be very great!
Happy hunting,
Briman
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Re: Tektites with Brown January 11, 2011 08:24PM |
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Registered: 3 years ago Posts: 261 |
If these were all found in the same general area, then they will certainly be Obsidian nodules due to two facts:
The brown one is certainly Obsidian of the variety (Or market name...) Mahogany Obsidian.
The gray spheres inside are certainly Cristobalite.
That being said, it is highly improbable that a few tectites managed to randomly fall in the same area as the other, certainly Obsidian pieces.
It would be like finding a random plastic apple at the bottom of an apple tree, mixed with the natural apples already on the ground, I should imagine ;)
-Bri
The brown one is certainly Obsidian of the variety (Or market name...) Mahogany Obsidian.
The gray spheres inside are certainly Cristobalite.
That being said, it is highly improbable that a few tectites managed to randomly fall in the same area as the other, certainly Obsidian pieces.
It would be like finding a random plastic apple at the bottom of an apple tree, mixed with the natural apples already on the ground, I should imagine ;)
-Bri
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Karie
Re: Tektites with Brown February 07, 2011 04:38PM |
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