2013-D Nickel Looks Gold!

That is just toning from circulation/air/how they were handled and what came in contact with the coin. I would keep A and put it in a Whitman album and see if the coin continues to tone with age. You might have a nice looking coin or it may stay the same. It only costs a nickel to see what can happen to it. Don't clean it up, just leave it as it is. In about 6 months you might want to flip the coin over. As sometimes the blue color might affect just one side.

Note the blue color is on just one side. What comes in contact or even previous cleanings can alter coins will show in time on coins stored in albums.
Here is a couple of silver coins that have been in the album for a while:

This coin was in a dansco album for about 10 years before I noticed it turn. Other coins around it did not do this, but why I'm not sure:

(The image was taken with a camera compared with images taken with a scanner.)

Even proof coins left in the older cellophane can tone. You can see the edges of the coins in a tube. Some can look great. I found a proof cent that turned gold in the last roll I bought.