Well actually, it isn't just dirt. I found it in a construction yard where people left iron equipment in the rain for a month. Iron oxide powder, looks pretty pure, very fine. I got about 3 kg. Now I'm wondering if I should ensure the purity of it, is extracting it with a magnet worth it, or shouldn't I bother? Do the ingredients for thermite need to be super pure?

Well actually, it isn't just dirt. I found it in a construction yard where people left iron equipment in the rain for a month. Iron oxide powder, looks pretty pure, very fine. I got about 3 kg. Now I'm wondering if I should ensure the purity of it, is extracting it with a magnet worth it, or shouldn't I bother? Do the ingredients for thermite need to be super pure?
Well, if its 50/50 dirt that's one thing, but if its 5% dirt that's another. Is super pure required? Not nearly.

use a magnet and wash to remove salts and use a magnet again ...

i find it easyer to simply stick the earth in a bucket with a hose in it usally a 5 gallon in my case and turn the hose to fill then turn it most the way off just enough stir up the bottom a bit and over fill then i smashed a hard drive took the high power magnet out put a bag over it and attached a string and swung around the inside of the bucket.... most the earthy mud gets washed out and the iron in the water moves around and should goto the magnet once out ... just pull the bag off the magnet over some paper .. and put under a hot 100 watt bulb or somthing and dry out

use a magnet and wash to remove salts and use a magnet again ...

i find it easyer to simply stick the earth in a bucket with a hose in it usally a 5 gallon in my case and turn the hose to fill then turn it most the way off just enough stir up the bottom a bit and over fill then i smashed a hard drive took the high power magnet out put a bag over it and attached a string and swung around the inside of the bucket.... most the earthy mud gets washed out and the iron in the water moves around and should goto the magnet once out ... just pull the bag off the magnet over some paper .. and put under a hot 100 watt bulb or somthing and dry out

nice too see your out of jail, its been a while since I posted around here

lol that was many many many moons ago hell im done my 3 years probation in january

A little bit of dirt really doesn't do anything to your thermite, maybe make it a little harder to light ... you won't be able to use it for welding, but I doubt that was what you were planning to use it for.