George Frederick Kunz,
The Curious Lore of Precious Stones
“ Black for men means gravity, good sense, constancy, and fortitude; for young women, fickleness and foolishness, but for married women, constant love and perseverance. The planet Saturn and Saturday are denoted by black. Strange to say, the diamond, the white gem par excellence, was selected to represent this sombre hue. Perhaps to offset this the animal chosen was the hog. As black was a mourning color, we need not be surprised that it typified decrepitude. ”
