✅ SOLVED What the 🦆

[beachhunter3]

Yeah, that's what I said when I finally got home and cleaned up what I thought was a coin cache box just to find out it was a piece of asphalt 😠... Anyway, I was shocked to see it after I cleaned it up and didn't know your metal detector would pick it up in fact it sings high tone like a coin and numbers like a coin... I know what you're thinking there's a coin inside but nope sure isn't. Actually, the bigger the chunk of asphalt the higher the number/tone. Has anyone else discovered this and any theories on why this is? Please help and I look forward to you guys input!

 

[ncsuwolf]

On the bright side…..it’s a very lovely piece of asphalt.

 

[beachhunter3]

Here's a bigger piece of asphalt I got just to see if my detector would pick it up and sure enough it did and sounds even more like a coin... What the hell man 😠... Any thoughts on why?

 

[creskol]

Could be any number of reasons really, but asphalt often contains both iron and manganese.

 

[Red-Coat]

Steel/blast furnace slag, both coarse and fine, is often used as an aggregate or filler in hot mix asphalt.

 

[beachhunter3]

Steel/blast furnace slag, both coarse and fine, is often used as an aggregate or filler in hot mix asphalt.

BINGO! That explains it...