Pigmented lesions of the eye GP Eyes Figure 2217 from Pigmentations of the Oral Mucosa and Facial Skin Semantic Scholar Melanocytic naevus (mole) on a patient's face. This skin mark is caused by a proliferation of the melanocytes, the skin cells that produce the pigment melanin. Moles vary considerably in size and Black and Brown: Non neoplastic Pigmentation of the Oral Mucosa Head and Neck Pathology Springer Nature Link