As there was no definite knowledge of the crystallography and chemistry of stones in the old days, writers referred to them often in general terms rather than by specific names, and these were translated into the names of later times according to the understanding of the translator, who had neither expert knowledge of his own nor reliable literature from which to gather information or guidance. An illustration of this general confusion occurs in the book of Job XXVIII. 18. It is written there, "No mention shall be made of coral, or of pearls; for the price of wisdom is above rubies." Scholars tell us that the words translated here "coral" and "pearls," signify "found in high places," and are thought to be precious stones though the variety is unknown. The Targum renders the first "Sandalchin," probably our sardonyx. Junius and Tremellius translated it "Sandaztros" in their Latin version of the Old Testament, whereas Pliny described it as a sort of carbuncle having shining golden drops in the body of it. After the same manner the last sentence, "For the price of wisdom is above rubies" is rendered by the great oriental scholar Bochart, "The extraction of wisdom is greater than the extraction of pearls," and other authorities agree with him. Although there is evidence that many if not all the precious stones of to-day were known and used by the ancients, it is equally evident that they were much confounded and very roughly classified by general appearance only, and as various peoples gave them different names, all records of them are as misleading as the recorders were ignorant of their differential qualities. Even with the rapid increase of knowledge in the last few centuries, not until quite lately has science drawn the lines clearly between stones similar in appearance though essentially different and furnished means for the detection of those inherent differences. It is impossible therefore to learn by ancient writings how long any of the precious stones have been known and used as jewels, for we do not know positively what the stone was by the name given in old writings or by the translator of them. The pearl only has not been thus generally confounded with other gems.