Hastings' Dictionary of the Bible (1898)
STONES, PRE'CIOUS. About twenty different names of such stones are found in the Bible. In many instances it is at present impossible to determine precisely what gem was intended by these names. This whole subject is one of great difficulty, for the mineralogy of ancient times was very vague and imperfect. The same word was often used for different gems or substances possessing some common property. Thus, "adamant" ("unconquerable") might mean steel, quartz, corundum, or any other very hard substance; "crystal" (kerach) meant either ice or transparent quartz.
The same ancient names were applied differently by different authorities, and even by the same writer. Even where a word has passed unchanged in form from Hebrew through Greek or Latin into modern use, it cannot be certainly concluded that the present application is the early one. The stones of the high priest's breastplate were engraved with the names of the tribes, Ex 28:21, but it is certain that at that time the art of cutting the harder gems was unknown.
According to Professor Maskelyne, a recognized authority, we must for this reason exclude from the breastplate the diamond, sapphire, emerald, and topaz. In place of these there may be substituted, respectively, rock-crystal (or chalcedony), lapis-lazuli, garnet, and chrysolite. The ruby and chrysoberyl would be too hard to claim a place in this list. Few diamonds were ever known of the size of these stones, which Josephus tells us were large, and which probably reached at least an inch square. T. See Jasper.
The sacred ornament of the high priest was probably broken up early in our era, but the gems which composed it are doubtless somewhere in existence in the Turkish empire or in Persia. It is not probable that all of these large engraved precious stones will always remain in obscurity. "What a source of rejoicing, both to archaeologists and, above all, to the religious world, will be the identification of even one of these venerable relics! " (See C. W. King's Precious Stones and Metals; art. ") In the very earliest times men set a high value on some of these minerals. Gen 2:12; 1 Chr 29:2.
The Tyrians traded in precious stones, which they obtained from India, Arabia, and Syria. Eze 27:16, Josh 11:22. Figuratively, the various gems are used in the Bible to emphasize such ideas as value, beauty, and durability, in Song 5:14; Isa 54:11-12; Lam 4:7; Rev 21:18-20; and passages already mentioned.