Amber is the subject of some curious legends under this name, but there is also a metallic electrum, sometimes called orbas by the French. Electrum is an alloy of gold and silver in the proportion of four parts gold to one of silver. The pale yellow color resembles amber.
According to Pliny, a cup of this metal has the property of discovering poison by exhibiting certain semicircles like rainbows in the liquor, which it also keeps sparkling and hissing as if on the fire. A black species of electrum or amber is the gar-gates spoken of by Pliny and the jet sometimes used in jewelry.