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
Rank in Judo Rank in Judo In Judo, improvement and understanding of the art is denoted by a system of rankings split into "kyū" and "dan" grades. These are indicated with various systems of coloured belts, with the black belt indicating a practitioner who has attained a certain level of competence. are ranked according to skill and knowledge of the art. Their rank is indicated by the colour of belt that they wear. There are two broad categories of rank: those who have attained a level of competency at which they are considered worthy of a and who hold grades and those who