Coinsandcanada.com

Found this while metal detecting sadly the salt has pretty much destroyed it

It musta been buried in a salt dump or where someone dumped his swimming pool chemicals or home water softener system. I remember I had to dump salt down in Oklahoma almost 40 years ago. It's hard to tell that's even a coin, let alone one you can read the date on.

I found a Mexican 10 peso coin on the beach in Mexico that looked similar to your coin the salt water ate it away