Blue Turquoise

Turquoise

Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium, with the chemical formula CuAl6(PO4)4(OH)8·4H2O. It is rare and valuable in finer grades and has been prized as a gemstone for millennia due to its hue.

Blue

Blue is one of the three primary colours in the RGB (additive) colour model, as well as in the RYB colour model. It lies between violet and cyan on the spectrum of visible light. The term blue generally describes colours perceived by humans observing light with a dominant wavelength between approximately 450 and 495 nanometres. The clear daytime sky and the deep sea appear blue because of an optical effect known as Rayleigh scattering. An optical effect called the Tyndall effect explains blue eyes. Distant objects appear more blue because of another optical effect called aerial perspective.

Turquoise (color)

Turquoise is a cyan color, based on the mineral of the same name.

blue

Adjective

1. Of a blue hue.
2. Depressed, melancholic, sad.

Noun

1. The colour of the clear sky or the deep sea; the colour midway between green and violet in the visible spectrum and one of the primary additive colours.
2. Anything coloured blue, especially to distinguish it from similar objects differing only in colour.

turquoise

Noun

1. A sky-blue, greenish-blue, or greenish-gray semi-precious gemstone.
2. A pale greenish-blue colour, like that of the gemstone.

Adjective

1. Made of turquoise (the gemstone).
2. Having a pale greenish-blue colour.