I have recently noticed several spots on my black cat's nose. At first I thought they were just dust spots, but they don't wipe off and have a slightly raised texture. He seems to have developed a few more since I first noticed them. They are not filled with an kind of pus. They are small and just slightly discolored from his normal black nose, probably around 10 bumps.
Should I be concerned about these spots? What might they be?