Jasmine: Hi, I'm Jasmine.
Chrissy: I'm Chrissy.
Jasmine: We're from NIU STEAM and...
Chrissy: You're listening to The Sound of Science on WNIJ.
Jasmine: Blair, while working in the garden of her DeKalb home, was wondering "what was used by different cultures to create dyes?" She knows they used items found in nature, but wasn't sure what they used or how they used it.
Chrissy: Light moves in waves that look like a wiggling Slinky and are organized in a spectrum depending on how fast the waves move up and down. The section of the spectrum, identified as visible light, contains the wave-lengths that we interpret as color.
Jasmine: This is exactly how dye works: Molecules, that make up the dyes, chemically bond to the materials that they are applied to, helping them stay in place and resist washing out or fading. The color of the dye we see are the wave-lengths of light they reflect. There are countless pieces of evidence that show that ancient cultues used dyes on textiles, in art and to make pottery, adorn structures, and identify status.
Chrissy: Past cultures would use the practice of boiling, soaking, or grinding to extract dyes from minerals, plant parts, and insects. For instance, indigo was obtained from plant leaves that were boiled and then set out to cool. Cochineal insects were first dried and then crushed to release a dark-red dye.
Jasmine: In some cases, the chemical make-up or color variations of dye can act as a piece of evidence to identify which culture the artifact may have belonged to. For instance, Mayans and Aztecs used cochineal insects to produce a rich-red color, while Egyptians used the root of 'rose madder' to produce a similar color. Greeks and Romans used the murex snail to produce a unique purple dye.
Chrissy: You have been listening to The Sound of Science on WNIJ, where you learn something new every day.
