Gargates
A black species of electrum or amber, now called jet. To electrum are attributed many occult virtues of a tell-tale character, and according to Pliny, a cup of this substance had the property of discovering poison, by showing certain half-circles, like rainbows, in the liquor, which also sparkles and hisses as if on fire.
Garinet, Jules: Author of a History of Magic in France, Paris, 1818. In this curious work will be found a description of the Sabbath, a dissertation on demons, a discourse on the superstitions connected with magic among the ancients and the moderns. 66