Color theory primary colors work at all is that the imperfect pigments being used have sloped absorption curves, and thus change color with concentration. A pigment that is pure red at high concentrations can behave more like magenta at low concentrations. This allows it to make purples that would otherwise be impossible. Likewise, a blue that is ultramarine at high concentrations appears cyan at low concentrations, allowing it to be used to mix green. Chromium red pigments can appear orange, and then yellow, as the concentration is reduced. It is even possible to mix very low concentrations of the blue mentioned and
Orange (colour) in Portuguese, and "orange" in English. The House of Orange-Nassau was one of the most influential royal houses in Europe in the 16th and 17th centuries. It originated in 1163 the tiny Principality of Orange, a feudal state of north of Avignon in southern France. The Principality of Orange took its name not from the fruit, but from a Roman-Celtic settlement on the site which was founded in 36 or 35 BC and was named Arausio, after a Celtic water god; however, the name may have been slightly altered, and the town associated with the colour, because it was on