If you notice any new pigmented growth on your skin or any changes in the appearance of an existing mole it may be melanoma. This is the most dangerous form of skin cancer. It develops in the cells that produce melanin (pigment responsible for your skin colour). This type of cancer can also develop in your eyes and in the intestine. Some symptoms include skin sore that fails to heal a flat red spot that is rough dry or scaly a shiny waxy smooth or pale lump etc. Mostly melanoma occurs in the areas that remain exposed to the sun