Explains in non-technical terms how to use the dichroscope to identify colored gems, and how to separate natural gems from imitations, treated gemstones, synthetics, and look-alikes. The approach i...
A darkening sky and a whitening sea, And the wind in the palm trees tall; Soon or late comes a call for me, Down from the mountain or up from the sea, Then let me lie where I fall. And a friend ...
The history of Sun Tzu's book, The Art of War, spans more than two millennia in the East. It has been the primary vade mecum of Generals, Kings, and Emperors since China's Warring States period in...