Help with color

I think the gray is just due to the image being under exposed, although the white balance is off a little too. What kind of lights are you using? I've noticed with LEDs that the white balance will change a bit depending on how close the lights are to the coin. Here's a quick edit. I just increase the exposure and contrast and reduced the saturation (although getting a correct white balance or shooting RAW would be preferred).

IMO it looks like a levels adjustment is all you need... set the "white" background to the white value in your image and voila!

I am really glad you like the camera and you look to be taking some great shots with it. I have tried a few and that model is the best point and shoot for close up shots I have found to date, and you can't beat it for the price in my opinion. You can almost touch the lens to the coin and it will focus and take a clear shot. I usually touch up the WB in a program if its still a little off but usually its close enough for me but I have used a program once or twice to correct the WB more

I could tell the white balance was off because of the greenish tint on the coin. Also, the left side of the image looks green and the right side more red. This is due to the different color temperatures of the lights you are using. It's probably best to just use one light or if you're using two or more, use the exact same bulb in each of them. You can also use a white sheet of paper to kind of do the job of a second light.

When I said it was underexposed, I just meant the picture was too dark. If you are using your camera's automatic exposure, it will base it's reading on 18% gray. Your coin and the white piece of paper are much brighter (this is the same reason snow pictures often come out gray instead of white). If your camera allows for exposure compensation, set that to plus 1 and see if that helps. Play with that setting until your background looks white.