"Chrystallomancy, by glasses..." -The Magastromancer xix, Gaule, 1652
"Precious stones were much used by crystallomancers in the past, the favourite stone being the beryl in pale sea green or reddish tints. By the ancients crystallomancy was practised with a view to the invocation of spirits." -Encyc. Occult, L. Spence, 1920