How does the jeweled beetle manage to look green despite not having any green pigment in their exoskeleton? Magic, that's how. Quick, someone go tell Traditional Chinese Medicine peddlers: they can cook up a new aphrodisiac.
Actually, there' a less magical, but still fascinating explanation: they sport microscopic cells in their exoskeleton that are almost identical to high-tech liquid crystals. The beetle appears green from certain angles because of the polarizing qualities of the crystals.
I'm looking forward to the next generation of LCD monitors being nothing more than a writhing mass of beetles strung across a metal frame. source source1