Nature's two dimension color image can be duplicated with just the transparent pigment colors magenta, yellow and cyan.
These primary pigment hues were important in painting through out time. From the earliest High Art period in 2000 B.C. when Arsinic was Yellow, Transparent Indigo and opaque frit were Cyan, and Karmes-Nacarat Carmine was Magenta. From then to the great vat pigments of today these colors can make any other hue. These three primary colors even in food color dye can make any color.
Incorrectly for the artist the computer's YMC/RGB light color wheel has cyan darking to green-black instead of blue-black. RGB has the same black path for yellow to get darker, it just subtracts light. To match pigments to elements, yellow should darken to match a banana getting brown and cyan should match the sky getting bluer, as the cyan crystals that show the darker mass colors of cyan as a deep blue.
Each of the Element=Crystal=Pigment Real Color Wheel's 36 rim colors has ten sections before becoming black. Yellow follows the color path of crystal compounds with iron, nickel, tungsten or titanium elements in them. Dark yellow is dark brown. The pure rim color yellow mixed with it's opposite color ultramarine blue becomes either a grayer yellow or grayer blue. The darker yellow color, brown, and ultramarine blue mix into a dark neutral dark that can be moved to either the warm or the cool side.
Here is background information on this color wheel.
http://www.realcolorwheel.com/colorwheel.htmYellow and magenta mix red, magenta and cyan mix blue, cyan and yellow mix green. Blue and yellow mix a shaded green because half of what is blue is magenta. The transparent primaries mix neutral black.
Mix a transparent yellow dark yellow with a transparent blue and you will mix a dark neutral. Remember, the darkest yellow is brown and lightens to yellow, like the Burnt Beechwood Bark pigment of a hundred years ago.
The old Red Yellow Blue color wheel theory can not make the primary hues of cyan and magenta, but yellow, magenta and cyan can make those colors plus any other color. This fact should be taught in all schools by ammending each State's School Standards.
The artists are ahead of the written recorders again.. And that's a good sign. It would be interesting to see the changes in our school art programs if students were provided with transparent colors in a water base medium using yellow, magenta, and cyan instead of the opaqueness of tempera paints and the wrong colorwheel they have to work with now!
In the old (still taught) Red-Yellow-Blue six color wheel complements mixed together make brown but not neutral dark. Yellow and purple make brown and won't make a neutral dark or gray, nice brown dark though. Red and green make browns and dark colors but not neutrals. Orange and ultramarine blue make brown. Orange and cobalt blue mix neutral. Cobalt Blue is half way closer to cyan than blue is - (Blue is Ultramarine Blue in pigments and is called Blue-violet in photography). It's a translucent hue in oil pigment.
Yellow, Magenta and Cyan are the only true primaries in pigments, and element gem crystals. A full color painting could be made just using just these three transparent colors.
Yellow is both a light and pigment primary color.
In pigments, a perfect opaque yellow hue is PY184, a Vanadate element. Vanadate is also the Standard Yellow in transparent crystal and on my RCW color wheel that matches light and crystal colors as they get darker.
Crushed crystals of that element are pigment. Chemical compounds of color elements are pigment.
The number for Yellow on the 36RCW color wheel is 36RCW#1.
Yellow is represented as transparent, translucent and opaque. The most important pigments to me are transparent and opaque. I can't find much use for translucent colors.
In light's RGB colorwheel this yellow primary color gets darker by subtracting the lights intensity. In pigments this is adding black to yellow, making a greenish hue, just like in light.
In pigment's transparent crystal, the dark base for yellow is red not green. Dark yellow is brown's red not green's. Artists mix opposite colors to make shadow colors.
In chemical pigments, and the crystals of Vanadate, Iron, lead (and many others), yellow becomes darker by adding brown. Crystals are the basis of this original 1995 Real Color Wheel for Artists.
Yellow and magenta make red, magenta and cyan make blue, cyan and yellow make green.
Here's how my youngest students learned it.
http://www.realcolorwheel.com/christmascamp.htmhttp://www.realcolorwheel.com/3rdGradePrivateColorLesson.htmIf a compound element makes only two crystals, they will be opposite colors on my color wheel.
Yellow in the crystal element Wavellite, shows yellow first darkening to brown than blue in a natural color progression. Many crystals show yellow darkening to brown like the Rutile crystal of Titanium, the Annuities crystal, Cassiterite and more. It's this darker color of yellow that mixes with ult. blue to produce neutral dark. Burnt umber and Ultramarine Blue mix neutral. That is yellow's dark and ult. blue's dark. Each of the 36 rim colors becomes darker in ten steps. Black is the eleventh step, the center.
LIMONITE is a secondary ore of iron that forms yellow to brown oxides. Brown is dark yellow.
About cyan and how it gets darker.
ALUMINUM in beryl excepts a lot of foreign chromates, just as it does in the corundum and spodumene compounds, Here is an aluminum light trick that is found in aquamarine, light cyan is seen from one direction and deep blue from a 90 degree off angle. Cyan gets darker and becomes Ult Blue, like the sky changes from cyan to ult blue.
CALCITE crystal, makes the perfect Cyan color with Copper in the Iceland Spar Crystal, it polarizes to the color Ultramarine Blue.