For 5,000 years the Golden Mean has been a central tenet of technology, and decoded by Fibonacci in the Middle Ages for the future exploitation of Dr. von Rosenstein and our Renaissance forefathers; the Fibonacci sequence is engraved upon the reverse

A flat, antiqued pewter, Renaissance-style scientific instrument pendant in the form of a Nautilus shell, with overlaid etched brass detail. The necklace comes on a 21"chain