Monsel's solution produces artifacts which can be troublesome if rebiopsy of a lesion is necessary. The tattoo produced can distort or obscure the basic pathologic process. It may lead an unwary pathologist into the false interpretation of the depth of a melanoma. Pathologists should recognize the artifact and we describe its characteristics. The use of Monsel's solution for hemostasis should be discouraged following biopsies of pigmented lesions or tumors which may prove to be diagnostic problems. The pathologist should be informed if Monsel's solution has been used.