Nikon D7000

Any advice as the best way to photograph coins? We are having trouble getting the color right while also having the pictures come out very sharp and detailed.

It would really be helpful if we knew what lens you're trying to shoot those coins with. Also, what lighting conditions are you shooting under? Your White Balance should be set to the light being used. It's in your manual.
And....where on the planet are you? North America? Africa? Europe?

Try Micro Lens, works for me.

Welcome...A light tent and tripod could be beneficial...

Some pics of what you have achieved could help...