How can you tell if the mole is cancerous?

my question is in regards to moles and mole types (cancerous and non). i understand that when doing a cancer self check you look for the A.B.C.D's. i remember reading somehwhere that if the mole evolves theres a problem. however i cant seem to find any information in regards to mole face and texture. the mole seems to have developed something almost regarding a crust and is dry. it is not however weeping. am i being paranoid or is it possible for a mole to peel or develop dry skin?