I Have A Coin That I Cannot Identify

The center of one side, the flower-like shape, seems to have been colorized in some way. So I guess this is the front side.

The 8 is strangely off-center (is there another number to its right?) and the leaves/feathers engraved in the center do not cover the whole center just a part of it.
Interestingly, there seem to be denticles (or teeth-like lines) around the rim?

We'd have to start from determining whether the 8 and the 5 (which I cannot really discern) are also engraved. Perhaps they were part of the design. Perhaps this was done not on a coin but on a round planchet.

Anyway, more / better photos could help.

I would say this is a colonial flat button that was once silver plated, but has been in the ground a long time, and the environment was not kind to it. The shank is off on the back and the silver plate is all gone on the reverse. The obverse has nice designs but no letters or number that I can see. Coins ought to have letters or numbers somewhere in the legend.