Original photographs by Ansel Adams are defined as photographs printed by Ansel Adams from the negatives he made (photographed and developed). Most will range between $4,000 and $70,000.
Keratosis is the term for any condition that is a benign overgrowth  and thickening of the epidermis.
The epidermis is a stratified, squamous epithelium that consists primarily of keratinocytes in progressive stages of differentiation from deeper to more superficial layers. The named layers of the epidermis include the stratum germinativum, stratum spinosum, stratum granulosum, and stratum corneum.