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Thermite Welding Powder? Or just a bunch of rust?!

Thermite Welding Powder? Or just a bunch of rust?!

Thermite Welding Powder? Or just a bunch of rust?!

(OP)
Trying to identify this bright orange powder turning up in a residential delineation.

Iron 70,000 mg/kg Aluminum 5,200 mg/kg Calcium 3,900 mg/kg Magnesium 1550 mg/kg Vanadium 125 mg/kg Arsenic 50 mg/kg

Just some rust? or maybe a thermite welding powder? Certainly an odd coloration Thinking it could be orgo-thermit's product http://www.orgothermit.com/downloads/THERMIT%20MSD...

RE: Thermite Welding Powder? Or just a bunch of rust?!

Need some context! Where did you find it? What was it near? Is it a lot or a little? Thermite welding is not common in construction other than heavy commercial, railroads or industrial. Can be used almost anywhere, just not common.

Why would you suspect Thermite powder? Arsenic??!

RE: Thermite Welding Powder? Or just a bunch of rust?!

(OP)
About 3,000 tons of construction debris and historic fill was dumped on-site during construction of this affordable housing complex built for Veterans returning from Iraq and Afghanistan. http://newyork.cbslocal.com/2014/06/11/da-veterans... There were arrests, but where all the stuff originated from is a mystery because the Defendants aren't talking.

I've seen handfuls of this stuff mixed in with every kind of burn product, brick, oily soil, block, car parts, rebar, timber you can think of. If I know what this is it helps me figure out where the stuff came from.

I'm thinking Thermit Welding powder because Orgo makes one with similar components: Iron, Aluminum, Vanadium, Maganese, and because the color was strange, bright orange.

RE: Thermite Welding Powder? Or just a bunch of rust?!

That explains a lot! Since Thermite is readily available, you might buy a sample and have it tested alongside the contaminant. This will help you validate the percentages.

You mentioned it was found with brick and other debris. Thermite welding molds sometimes look like brick after they are broken up.

You might check to see if there was a contractor in the area who does railway repair work or even check to see if the local municipality does such if there are commuter rails operated by the municipality or nearby municipalities.

I believe the arsenic might be an extraneous contaminant; however, you can determine that by testing a clean sample of Thermit powder.

Keep in mind that if this is Thermit powder, it can be dangerous and the combustion process can be started in a variety of ways.

There are investigative techniques, similar to DNA analysis, that can help identify the source of many materials, even inorganic ones. Organic materials are a bit easier though.

Good luck.

RE: Thermite Welding Powder? Or just a bunch of rust?!

(OP)
Hah, Thermite Welding Mold - that might explain this fragment I picked up the first time we saw this kind of material. Didn't look like any brick I'd ever seen.


Link

RE: Thermite Welding Powder? Or just a bunch of rust?!

PJ...quite possibly a fragment of a mold. Since it was dumped there from another location, it is likely only a small fragment.

Have you located any rail repairs in the area or contractors who do such?

Also, do you have a photo of the material you found? Keep in mind that if the material was only rust or mill scale from steel, it would not likely have aluminum in any appreciable quantity mixed with it.

Also, the material percentages don't come close to 100, what was the rest of the material in the sample?

RE: Thermite Welding Powder? Or just a bunch of rust?!

Thermite has approximately 25% aluminuma so it is not thermite. The aluminum is what burns and gives off the heat.

The thermite molds are manufactured from ceramics, not thermite. The thermite would be a coating on the mold.



Don't think this would be considered hazardous.

RE: Thermite Welding Powder? Or just a bunch of rust?!

(OP)
Maybe Lawrence Aviation Link, a supefund site now,Link and a site the trucking company involved here is already associated with. Link

A pic of the thermite welding the LIRR was doing, would have been done there, too. Link

I know the aluminum concentration is wrong for straight up thermite powder, but I keep coming back to the fact that Orgo-Thermite supplements aluminum its powder with maganese and vanadium. Link

I didn't take a picture, but it looks like this Vanadium Pentoxide Link

I'm going to be doing some more profiling so I'll keep you apprised. Whatever it is, I wouldn't want my two year old rooting around in a hole I dug out for a shrub and putting this in his mouth. Thanks for the help!

RE: Thermite Welding Powder? Or just a bunch of rust?!

(OP)
Oh, wait, it looked just like this:

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