Are black moles dangerous? What do they mean?

Moles . While not all black moles are skin cancer, very dark or black pigment is found in many melanoma skin cancers . See a dermatologist for any suspicious mole.
Sometimes. Aad malignant melanoma: asymmetry: 1 half is unlike the other. Border: irregular, scalloped or poorly defined. Color: varied with shades of tan, brown or black; or white, red or blue. Diameter: > 6 mm. Evolving: mole /skin lesion looks different from the rest or is changing in size, shape or color. An irregular mole that itches, bleeds or is painful is worrisome for possible cancer.