As early at least as the ith century the art of extracting a blue pigment from lapis lazuli was practised, and from the beginning of the 16th century this pigment began to be imported into Europe from "over the sea," as azurrum ultramarinum.
The composition of the pigment is quite similar to that of lapis lazuli; but the constitution of both is uncertain.
The Arabian geographers of the 10th century speak of its mines of ruby and lapis lazuli, and give notices of the flourishing commerce and large towns of Waksh and Khotl, regions which appear to have in part corresponded with Badakshan.
In any large collection of fragments it would be easy to find eight or ten varieties of opaque blue, ranging from lapis lazuli to turquoise or to lavender and six or seven of opaque green.
Acting upon that theory, the experts of TokyO and Nagoya have produced many very beautiful specimens of monochrome enamelyellow (canary or straw), rose du Barry, liquid-dawn, red, aubergine purple, green (grass or leaf), dove-grey and lapis lazuli bl,ue.