Secrets of the Gem Trade 2nd edition quote was the gem of choice

was the gem of choice for engravers from the Bronze Age until late Roman times

12 Emerald was considered to protect the wearer against all manner of enchantments

From the reviews of the first edition: "The book presents in a systematical manner the experimental and theoretical data on optical properties of diamond accompanied by short explanations and models

Materials with density close to tungsten

to be the most precious gem of all

Secrets of the Gem Trade 2nd edition quote was the gem of choicePART I, Chapter 1 Becoming A Connoisseur: Essentials Imagine a time before the existence of the world we know, long before the invention of artificial colors, aniline dyes or LED lighting. Picture a group of our remote ancestors, a party of Neolithic hunters, clothed in animal hides and armed with spears, picking their way single file, across a shallow mountain stream. One man stoops to drink. Out of the corner of his eye, he catches a tiny flash of