Chocolate Bloom
Chocolate bloom has nothing to do with chocolate and flowers. Actually, it really is not as pretty as it sounds.
An example would be when you bought yourself a chocolate candy bar only open it to find a strange white tint on the exterior of the chocolate. The appetizing deep brown color is completely gone.
This white staining on your chocolate is called chocolate bloom.
Chocolate bloom occurs when your chocolate has been exposed to temperatures not conducive for keeping it in the best quality. Typically this happens when the chocolate had been exposed to heat on a hot summer day with no adequate air conditioning keeping it from losing its color aesthetic appeal. This can also occur if the chocolatier did not properly temper the chocolate when it was made.
The bloom itself does not necessarily mean the chocolate has gone bad, or rather that it has lost the proper crystallization to keep it looking delicious. However, if you take a bite and the texture is nowhere near what you would have wanted, then indeed the chocolate has expired.
If you have a solid hunk of chocolate, you could try to melt the chocolate and bring it to temper to try and save it. However, if you don’t have the time, I would not fault you to just get another one. ;)