Not sure why you would want to since you would have no discrimination or target ID and it is very sensitive to ANY metal (so bits of iron trash would drive you nuts), but sure, you can use it for that. I guess if you were looking for possibly more depth at the expense of any discrimination it would be a viable option . . . . . but then again, if you really want depth at the expense of discrimination, why not look at a GP 3500 (only kidding)?
Personally, I would opt for minimal discrimination in the Coins & Treasure mode and not be bothered by every little flake of metal the coil comes across. If you want to hunt with no discrimination, at least you will have target ID in this mode to help you decide if a target is worth recovering or not.
I guess an option is to hunt in the Prospecting mode and toggle over to the Coins & Treasure mode with the All Metal pattern to ID targets but it seems like a lot of work for most areas.
Andy Sabisch