the Greek, σμήρις (smeris). There are different views in classical rabbinical literature as to the order of the names; the Jerusalem Targum, for example, argued that the names appeared in the order according to which they were born. Maimonides describes the jewel stones arranged in four rows, saying that on the first stone belonging to Reuben were also engraved the names of Abraham, Isaac and Jacob, while on the last stone belonging to Benjamin were also engraved the words "the tribes of God"; kabbalistic writers such as Hezekiah ben Manoah and Bahya ben Asher argued that only six letters from each name were present on each stone, together with a few letters from the names of Abraham, Isaac, or Jacob, or from the phrase "[these are] the tribes of Jeshurun", so that there were 72 letters in total (72 being a very significant number in Kabbalistic thought). There was also a different order for the names inscribed on the two "onyx" stones, carried on the High Priest's shoulders. One opinion suggests that the names of the twelve tribes were arranged in groups after their mothers: Leah's six sons aligned one after the other on one stone, with Judah heading this list, followed by Rachel's sons with the names of the concubines' sons interposed between the two sons of Rachel. Unfortunately, the meanings of the Hebrew names for the minerals, given by the masoretic text, are not clear, and though the Greek names for them in the Septuagint are more clear, some scholars believe that they cannot be completely relied on for this matter because the breastplate had gone out of use by the time the Septuagint was created, and several Greek names for various gems have changed meaning between the classical era and modern times. However, although classical rabbinical literature argues that the names were inscribed using a Shamir worm because neither chisels nor paint nor ink were allowed to mark them out, a more naturalistic approach suggests that the jewels must have had comparatively low hardness in order to be engraved upon, and therefore this gives an additional clue to the identity of the minerals. Others suggest that they were engraved with emery, having the similar property of a diamond used in cutting other stones and which was called in Greek σμήρις (smeris). Explanation of the symbolic meaning of the jewels generated a great deal of both Jewish and