Magnetic Rocks

When I used to work in Toronto many of the rail lines used iron smelter slag as ballast.

Bits of slag get carried away by what ever and certainly bring false hopes at times !

Cheers

Derek

I spent this afternoon looking for monuments on a small car wash site. Every tiny bit of ferrous metal in the ground on this site sings like a refrigerator magnet. I've been on other sites where large pipes and rebar give almost no signal at all. I've always wondered if there's something about soil conditions or other environmental factors that make some pins sing and others not so much.