Human skin color the liver. On lighter to medium skin tones, solar lentigenes emerge as small- to medium-sized brown patches of freckling that can grow and accumulate over time on areas of the body that receive the most unprotected sun exposure, such as the back of the hands, forearms, chest, and face. For those with darker skin colors, these discolorations can appear as patches or areas of ashen-gray skin. Melanin in the skin protects the body by absorbing solar radiation. In general, the more melanin there is in the skin the more solar radiation can be absorbed. Excessive solar radiation causes direct and
Minium (pigment) 300 B.C. It was known in the Han Dynasty (200 BC-200 AD) under the name "cinnabar of lead" ("ch'ien tan"), The process of manufacturing it was described in a Chinese manuscript of the 5th century. Minium was widely used for Persian miniature painting and Indian miniature painting. Minium (pigment) Minium, also known as red lead, is a bright orange red pigment that was widely used in the Middle Ages for the decoration of manuscripts and for painting. It was made by roasting white lead pigment in the air; the white lead would gradually turn yellow, then into an orange lead