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
Pigment carmine was popular in Europe, blue remained an exclusive color, associated with wealth and status. The 17th-century Dutch master Johannes Vermeer often made lavish use of lapis lazuli, along with carmine and Indian yellow, in his vibrant paintings. The earliest known pigments were natural minerals. Natural iron oxides give a range of colors and are found in many Paleolithic and Neolithic cave paintings. Two examples include Red Ochre, anhydrous FeO, and the hydrated Yellow Ochre (FeOHO). Charcoal—or carbon black—has also been used as a black pigment since prehistoric times. Two of the first synthetic pigments were white lead (basic lead