Under the name of false or artificial pearls are understood at present small beads, so prepared by art as to approach very near to real pearls in shape, lustre, colour, and polish. It appears that in Pliny’s time such were not known, else he certainly would have mentioned them. The invention was not easy, and this difficulty to imitate pearls has contributed, with the reasons before mentioned, to keep up their value. It would seem that at first, hopes were entertained of finding a method to make large pearls from small or broken ones. Tzetzes speaks of this imagined art, and receipts for that purpose have been still retained in various books, where they fill up room and amuse the ignorant; for it is hardly possible to give to the pulverised calcareous matter sufficient hardness, and that lustre which belongs only to the surface of real pearls, and which, when these are destroyed, is irrecoverably lost. More ingenious was the idea of making pearl-coloured glass beads of that kind called _margaritini_[778]; but it excites no wonder that this was not done earlier, although the art of making coloured glass is very old; for opal colours are obtained only by a skilful process and the addition of putty, bone-ashes, and other substances. Still earlier was the invention of making hollow glass beads, which were incrusted on the inside with a pearl-coloured varnish. This method was first pursued, as far as I have been able to learn, by some artists at Murano; but their invention seems to have been considered by the government as too fraudulent, and was therefore prohibited, as we are told by Francis Massarius, who lived in the beginning of the sixteenth century at Venice, and must therefore have had an opportunity of knowing the truth of this circumstance[779]. Some say that an amalgam of quicksilver was used for these pearls; and if that was the case, the object of the Venetian prohibition was rather of a medical nature. After this, small balls of wax or gum were covered with a pearl-coloured enamel. These were praised on account of their lustre; but as their beauty was destroyed by moisture, they did not continue long in use[780]. A French bead-maker, however, named Jaquin, at length found out the manner of preparing the glass pearls used at present, which excel all others, and which approach as near to nature as possible, without being too expensive.