blue green

blue green
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it is a strong blue-green.　R0 G127 B137
Japanese says heki.

sakura

sakura
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1 a light shade of red. 
2 any of numerous trees and shrubs producing a small fleshy round fruit with a single hard stone. 
3 horsemea
4 R253 G217 B217
Japanese says sakura.

natural color

natural color
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Japanese says ten-nen-syoku

iridescent

iridescent
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the visual property of something having a milky brightness and a play of colors from the surface
Japanese calls Tama-Mushi-Iro.