A blue nevus is usually raised and looks like a dome. It can be dark blue to almost black in colour.
Occasionally, a melanoma may look very similar to this type of mole (See photograph).
If your doctor is concerned, then a dermatoscope examination will confirm what type of mole you have. However, in some cases, a biopsy may be necessary to make absolutely sure.
A blue nevus should be positively identified every time by your doctor to confirm that it’s not a melanoma.