It's a nice piece of artwork, good job MSM!
I have a few pieces of constructive criticism I'd like to add however:

The coin doesn't really match Graal's perspective. Graal's perspective is at an angled bird's-eye view, which you'll see examples of in level tilesets, in which you can see the front end of a table and on top of it too for example.
Your coin seems very flat and two dimensional, which would make it seem like a part of the floor if it were placed in a level, and not actually like an upright coin.
To fix this issue, I suggest you add a top to your coin to make it look more three dimensional.

Also, your coin is all the one colour, which really doesn't make it seem too metallic as you'd expect a coin to be. Try to alternate between lighter shades of yellow in an attempt to match the metallic "sheen" you'd get off a coin.

Otherwise, keep it up! I like it.