Something i've found while metal detecting

reply to post by SpringHeeledJack


ETA: Check it against these OP

en.wikipedia.org...

en.wikipedia.org...

www.google.com...:&imgrefurl=http://www.ux1.eiu.edu/~cfjps/1300/igneou s_images.html&docid=f9f4i5rVn5yDFM&w=634&h=414&ei=JGY0TsTKBcbSiALympmwCA&zoom=1&iact=hc&vpx=898&vpy=249&dur=408&hovh=181&hovw=278&tx=93&ty=135&page=2& tbnh=167&tbnw=228&start=10&ndsp=10&ved=1t:429,r:8,s:10

reply to post by Silend


To me it looks like some things we find around old foundries and ironworks here in Alabama. Basically stuff melts from the high temps and sometimes it forms stuff like what you have, bubbles and all. Not sure if it's waste material or just something from the landscape that happened to melt ( and no I am not talking about modern ironworks, I am talking the ollldddd type like in Tannehil State Park), or even a part of the furnace itself. So that would make it a piece of... glass?

eta- link about old ironworks: www.alaironworks.com... - we used to go to Tannehil a lot on school field trips! There and Moundville.

reply to post by Silend


I couldn't tell you for sure. All the pieces I found were too small to really guess and any speculation would be just that... a guess. If I have to though, I would say it's about it's weight in glass if you can imagine. Maybe slightly heavier.

ETA: If you're so inclined, you can work out the chemical equation to find a molecular weight and use that, along with volume to compare it to your rock but that's more time than I'm willing to put in. Not to mention to only molecular composition I can find for it is given in percentages without saying if it's percent mole/mole ratio or percent by mass. This gets a little confusing...


ETA2: I see... The molecular mass is variable dependent on inclusions of Magnesium and Iron. There's really no way to know.

Ok, another thing, i just looked up in wikipedia en.wikipedia.org... and they say that Obsidian can be found in locations which have experienced rhyolitic eruptions, but we dont have any eruptions here

Looks like coal slag to me

www.flickr.com...

en.wikipedia.org...

reply to post by Cohort


Thank you! I was trying to figure out exactly what it was called. Certain places here are littered with the stuff from I actually have a few pieces, and am debating whether or not its worth the trouble to upload some pics

i think it looks like hardened tar, hold a lighter or lit match to it and see if it melts or softens. roofing tar becomes brittle when cold and will flake off like flint or obsidian. after reading entire post , with the brown and green striping, its probably obsidian.

Take a hand torch and see if it burns..
If it melts as it burns its tar for roofing if it burns its coal
If it wont light its glass
Or obsidian

I thought I would toss out the possibilities of tektite, or moldavite, which are essentially glass formed from the impact of an object from space. While moldavite is typically a dark green, I have seen specimens which were mostly black. It's vitreous, or glassy. (Well, it is a form of glass). Tektite is usually pitted, but again, can sometimes be smooth. So. Does it have any green in it if you hold it up to the light? Also, use a magnifying glass if you don't have a jeweler's loupe. You can google each one for pictures.

If you can rule out tektite or moldavite, then I agree it's obsidian. Obsidian is nice, and is sometimes used in jewelry. Keep it, and if it were me, I'd return to see if I could find some more.

I've seen many objects like the one in the OP. I've even inadvertently made a few of my own.

It's a melted beer bottle. Empties get tossed into the camp fire and melt.

reply to post by Cohort


Same here, that's the first thing i thought.

I found something similar one time while metal detecting, but it looked a bit more like iron. At first I thought it was a meteorite, but eventually I came to the conclusion that it was just a hunk of iron ore that looked like a rock. The metal detector picked it up, and it had very faint magnetism, so it was kind of weird.

That kind of does look like a meteorite to me, but if it wasn't detected by your detector, then there is a good chance it is not. You didn't happen to have your device set to discriminate iron did you? Whatever it is, it looks cool.

Obsidian is pretty black- around here we've got an old glass plant and I find a lot of that in the area. It's kinda a muddy brown purple looking rock- I think they call it glass slag rock.

reply to post by Silend

If there is a college near you take it to the geology teacher they will help you identify it.

Hard coal.
or
Obsidian.

My first thought was obsidian as well.

I thought obsidian too, but obsidian should be only slightly heavier than glass. As far as flint arrowheads they also made arrowheads out of obsidian and I thought that was in part because it was found in thin pieces. That's a big piece. I would echo the advice to take it to a geology professor or student and see what they say.

Obsidian no but close

Its clinker glass from a old coal fired steam engine.

At the end of the day the locomotive fireman would take a long hooked steel rod and put it down of what was left of the burning coal in the fire box and turn it rolling up a ball of glass left over from the burned coal.
Common along old railroad tracks or old coal boilers.

sometimes the Fireman would stoke the fire box on one side and after the coal burned down on the other side he would hook out a glob and just flick it off the moving train.
Many times this would cause fires along the tracks.
In kansas this caused major fires in wheatfields.
This was one of the reasons many farmers helped the James-Younger Gang in the American midwest.

reply to post by Novise


Actually, they started with large "blanks", sometimes up to a foot long and 6-8 inches thick. The flakes that would come off would be used for scrapers or other low tech tool. Kinda neat piecing together a "trash" site and seeing how many of the pieces actually came from the same rock. Anyways, my thoughts are a form of glass, and not the volcanic kind (obsidian).

If you say there's no volcanoes around....can kinda eliminate obsidian. Although, in ancient times (pre-history) natives traded it like it was gold. In America, they've found pieces of obsidian down in Central America that can be traced to the Northeast United States area.

Oh this thread is so much fun for me! I'm not about to contradict what anyone has already said, but I can add a bit of information that could be relevant to your investigation.

Your photo brought back memories of something I used to play with as a little child before we moved. I did a search for it and found out that the Baltic holds a large portion of the world's supply. The item that's found in abundance near the Baltic Sea is called amber /copal. Amber is fossilized tree resin, whereas copal is not, I believe. In older homes or flats, (the pre-1970s ?) orange and or black chunks of it were commonly used in fake fireplaces seen in apartments and poorer homes such as my parent's place. Thus I used to play with the rocks and line them up on the floor until someone ended my fun. I haven't found where it was used in in fancy train parlours, but it was most likely sent to markets by train, I should imagine. Here's what some looked like, although ours were either orange chunks or black chunks that had tiny streaks in them sometimes.
bin picture
There's a whole culture around Baltic amber from medicine to jewellery, folk tales, etc. Some interesting reading on it here and harvesting of amber picture lower down on page

Here's a link to a pic of raw black resin. pic here
Wiki page on all kinds of amber here.
Another pic.

Now you have lots of possibilites as to what your find is.
I would also encourage you to consult with a geologist in your area.
Now don't go away and keep us in suspense. Come back and tell us what it really is, ok?