Decoration of the Breastplate of the High-Priest

When Moses wished to engrave on the stones of the breastplate the names of the twelve tribes of Israel, he is said to have had recourse to the miraculous shamir. The names were first traced in ink on the stones, and the shamir was then passed over them, the result being that the traced inscriptions became graven on the stones. In proof of the magical character of this operation, no particles of the gems were removed in the process. (Ginsburg, "Legends of the Jews," Eng. trans., Phila., 1909, vol. i.) The name really designates "emery."

An argument against the use of especially rare and costly stones in the decoration of the breastplate has been found in its probable size. (See J. L. Myers in the "Encyclopaedia Biblica," vol. iv, pp. 4799-4812.) We are told that when folded it measured a span in each direction, and this would indicate that its length and breadth were each from eight to nine inches. In this case the stones themselves might have measured two by two and a half inches, and, in view of the number of characters required to express some of the tribal names, these dimensions do not seem excessive. It is highly improbable that in the time of Moses precious stones like the ruby, the emerald, or the sapphire would have been available in these dimensions. The difficulty of engraving very hard stones with the appliances at the command of the Hebrews of this period must also be taken into consideration. As we shall see, however, there is good reason to believe that after the Babylonian Captivity a new breastplate was made, and at that time it may have been easier to secure and work precious stones of great value and a high degree of hardness. We must also bear in mind that in those periods perfection was not so great a requisite as rich color.

In his commentary on Exodus xxviii, Cornelius a Lapide (Cornelius Van den Steen) discusses the question of the diamond in the high-priest's breastplate. In the first place, he notes that the diamond was very costly, and that a large stone would have been needed to bear the name of Judah or that of any other tribe. He considers that a stone of the requisite size would have cost a hundred thousand gold crowns, and he asks, "Whence could the poor Hebrews have obtained such a sum of money, and where could they have found such a diamond?" He proceeds to give still another reason for doubting that the diamond was in the breastplate,--namely, that it would have marked too great a distinction between the tribes, the result being that the tribe to which the diamond was assigned would have been puffed up with pride, while the others would have been filled with hatred and envy, "for the diamond is the Queen Gem of all the gems." (See Gimma, "Della storia naturale delle gemme," Napoli, 1730.)