HISTORICAL EVIDENCE 11.1 The Color of Kings

Purple is a color (hue) often associated with royalty. The history of this association traces back to the early Babylonians and the later Phoenicians and is related to one of the earliest commercial products, a natural dye extracted from mollusks and called Tyrian Purple, Royal Purple, Imperial Purple, or Ancient Purple (6,6-dibro-moindigo). The name Tyrian refers to the city of Tyre in Lebanon, where production was centered. The preparation of the dye was labor intensive and required the extraction of tiny amounts of precursor chemicals from thousands of mollusks. Because of labor and material costs, the dye was literally worth more than gold thus. Kings were the only ones who could afford it 

Sources Florence, D., Spectral Comparison of Commercial and Synthesized Tyrian Purple, Modem Microscopy, November 18,2003. 

Zollinger, H., Color A Multidiscip linary Approadi. Zurich Wiley Verlag, 1999. 

The pigment particles in most white paints are between 0.2 and 0.4 /am in size. Why  

Answer This size corresponds to 200-400 nm. Scatterir is maximized when the particle size is approximately half their wavelength, so these particles will effectively scatter light in the 400-800-nm range, the range of visible wavelengths. 

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