1 Coil (chemistry), a tube used to cool and condense steam from a distillation.  Coil spring, used to store energy, absorb shock, or maintain a force between two surfaces.
Umber RGB Color Code: #635147. The hexadecimal RGB code of Umber color is #635147. This code is composed of a hexadecimal 63 red (99/256), a 51 green (81/256) and a 47 blue component (71/256). The decimal RGB color code is rgb(99,81,71).
Sienna is lighter in shade than raw umber, which is also clay with iron oxide. but which has a higher content of manganese (5 to 20 percent) which makes it greenish brown or dark brown.When heated, raw umber becomes burnt umber, a very dark brown.The clay soil of Tuscany (here near Monteriggioni) is rich in limonite, or hydrated iron oxide, the main ingredient of sienna pigment. Limonite, a clay containing iron oxide, which gives the color to sienna pigment.Haematite.long with ochre and umber, it was one of the first pigments to be used by humans, and is found in many cave paintings. Since the Renaissance, it has been one of the brown pigments most widely used by artists. The first recorded use of sienna as a colour name in English was in 1760.