In the sixteenth century jet was popularly called “black amber,” and Cardano states that in his time beads of this material were made up into rosaries. He also says that curious figures made of jet were brought from Spain to Italy.[397] Many are unaware of the fact that a number of ornamental objects made of nephrite and jadeite—unquestionably of European origin—are to be seen in the quiet little town of Perugia. These objects, collected principally in central and southern Italy, constitute the Belucci Collection, in that city. This collection also contains other specimens of worked jadeite, which must have been brought to Europe at the time of the Spanish conquest of Mexico and Peru. A very interesting example shows us the utilization of a pagan celt to form a Christian emblem. By the removal of a rectangular piece from each of the four corners of the jadeite celt, a perfect cross has been made, the back and front of which still offer the original polish given to the material centuries ago by the native American worker. The superstitious belief propagated in Europe by the returning Spanish sailors, very probably an invention of their own to enhance the value of their jade and jadeite, that these minerals were worn by the natives as a cure for diseases of the kidneys, whence the name _lapis nephriticus_, rendered the material exceptionally precious in the eyes of many, and quite possibly it may have been thought that, by transforming this object into the sacred form of the cross, a talisman would be produced that would not only effect the cure of a special disease, but would also by its superior virtue guard the wearer from harm and danger of all kinds. Here may also be seen some celts of European jade sewed up in little bags to be worn on the loins. [Illustration: 1. Cross made from a celt of jadeite (Mexican), bought from a peasant in Perugia. This was originally a celt and was divided into four pieces. Of Mexican origin and brought to Italy in sixteenth century. Belluci Collection. 2. Jadeite celt, from Guatemala. 3. Celt, Aboriginal. A small stone hatchet made of jade nephrite, of the kind believed by the peasants to be thunderbolts. Mounted in silver to be worn as a charm. This specimen, tied over the loins, is said to have been worn as recently as fifty years ago by a Scottish gentleman as a cure for kidney disease. British Museum.]