The stones called Idæi dactyli,[1] and found in Crete, are of an iron colour, and resemble the human thumb in shape. The colour of icterias[2] resembles that of livid skin, and hence it is that it has been thought so excellent a remedy for jaundice. There is also another stone of this name, of a still more livid colour; while a third has all the appearance of a leaf. This last is broader than the others, almost imponderous, and streaked with livid veins. A fourth kind again is of the same colour, but blacker, and marked all over with livid veins. Jovis gemma[3] is a white stone, very light, and soft: another name given to it is "drosolithos."[4] Indica[5] retains the name of the country that produces it: it is a stone of a reddish colour, and yields a purple liquid[6] when rubbed. There is another stone also of this name, white, and of a dusty appearance. Ion[7] is an Indian stone, of a violet tint: it is but rarely, however, that it is found of a deep, full, colour.