Dermatologist said a mole that had an diameter of more than 6mm( one of abcdes of melanoma) was normal. is this possible?

Constellation: what makes a mole suspicious for malignant melanoma is a constellation of criteria. It may be that size was the only characteristic in question.

Please consult with a Dermatologist Doctor who can give you a through examination and the correct recommendations and treatment. If you are not confident in your Doctor see another for a second opinion.