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We are all familiar with color produced from dyes. Dyes use the electrons in their atoms to control the colors they reflect. A blue dye reflects blue and absorbs all other colors because the particles reflect the energy from the blue wavelengths and absorb all other wavelengths.

In structural color, the material is actually colorless, but light is scattered in such a way that certain wavelengths get amplified and reflected through constructive interference. Opal is an example of this. Opals are made of silica spheres about 200 nanometers in diameter. Silica is colorless, but when the spheres are arranged in a particular pattern the light is scattered, and wavelengths constructively interfere in different positions giving color. Each wavelength produces a different color at a particular position. Structural color cannot be bleached or changed unless the very structure of the mineral is changed.

This color production is called isotropic structural color because it depends on the angle of viewing. The structure of the material determines the color. Peacock feathers, bluebirds, and morpho butterflies are living examples of structural color. It is also seen in some plants. There is great interest in this method of producing color because it will not change with time and does not require harmful dies to produce.

We are all stirred by the beauty of the world around us, and God's wisdom and intelligence are displayed in many ways. As we grow in our understanding of what God has done, we continue to be amazed at the complexity of God's world and of the wonder-working hand that has gone before us.

Our thanks to Dr. Matt Meredith, who sent us this information taken from Chemical and Engineering News.

Picture credits:
Roland Earnst.
© viktoriya89. Image from BigStockPhoto.com.