Color Oppositions
Yellow and Blue

Yellow is the undertone of brown as with the water color pigment of old, Burnt Beechwood Bark,
the organic plants "Turmeric" root and "curcuma" root, from India. Yellow to brown is also stated with the crystals WAVELLITE and VESUVIANITE and many others.

It takes two transparent oppositions to mix neutral
or one transparent and one translucent color,
two translucent colors, or one transparent and one opaque.
Two opaque colors just won't make a real dark neutral.

Top-tone is adding White to the color.
Under-tone is adding clear.
Mass-tone is thick out of the tube.
Transparent is clear like colored glass.
Translucent is floating colloidal compounds of colored elements.
Milk is translucent.
Opaque is dense and light blocking, like a rock.
YYYY = As Yellow as you can get,
MMMM = pure Magenta
MMCC = Ultramarine Blue
CCCC = Thalo Cyan Blue

WAVELLITE, Al3[PO4]2[OH,F]3.5H2O, H3.5, SG-2.36, orthorhombic crystal system, acicular,
like the needles of Rutile suspended in clear crystal, only these needle crystals form a dense rocklike mass.
ALUMINUM, yellow, brown, blue, centering standard, transparent.
Aluminum really does it big this time, each needle starts at the center radiating outward,
concentrically ringed bands form around the center,
each band ending as a cleavage line, twenty or so bands per complete needle crystal.
The band itself can change from clear transparent to opaque white while in the center,
the second band range is transparent yellow crystal, than brown, than blue.
From brown to blue, the crystal can change into an aggregate and lose it's crystal properties.
THIS MINERAL PHOSPHATE CRYSTAL SHOWS THE DEEPENING OF YELLOW TO BROWN AND
BROWN TO BLUE, LIKE MY REAL COLOR WHEEL FOR PIGMENTS.