This last remark suggests the reason why Tavernier did not mention the sum demanded by the Banian for his diamond. Possibly the long-headed peddler feared that had he stated the amounts his readers might not have deemed his profit quite so honest. Can this be the reason, moreover, of his total silence regarding the purchase of the Blue Diamond? It seems the fate of this stone to come from out of the Unknown in a mysterious fashion. We shall meet it, appearing suddenly and without a history. Tavernier gives three drawings of this Blue Diamond, which was, he said, clear and of a lovely violet hue, and its weight in the rough was one hundred and twelve and one quarter carats. There is no other example of a blue diamond of this deep tint known--a fact which went far to establish the identity of the Blue Diamond in aftertimes. Diamonds of all the colors which belong of right to other precious stones are occasionally found. Thus they are red, green, yellow, and blue. The first and last named tints being the rarest, while the yellow is decidedly common. The true diamond, however, no matter what may be its hue, has an iridescent brightness which no other gem can counterfeit. This iridescence, coupled with its hardness, forms the test of the diamond; and its absence never fails to reveal the nature of an impostor. If anything can scratch a stone, that stone is not a diamond. The writer, in common with all her schoolmates, once bestowed a great deal of admiration and no small portion of envy upon a young companion on the strength of that young companion's diamond, a lustrous gem of most remarkable size. Alas! our admiration was undeserved and our envy misplaced. That splendid diamond had upon its upper surface three deep scratches! [Illustration: TAVERNIER'S BLUE DIAMOND.] [Illustration: THE "HOPE BLUE" DIAMOND.] But to return. When Louis XIV. bought from Tavernier at, we will say, an "honest profit" to the seller, that three millions' worth of precious stuffs and stones, he became possessed of the Blue Diamond. This was in 1668 when the king was in the full tide of his glory, and also of his extravagance, conquering provinces, building palaces and buying gems. There seems to be no record of the first cutting of the Blue Diamond, if indeed it was cut at all during the reign of the "Grand Monarque." And what is still more strange, it seems to have attracted very little attention, its heaven-blue tint being perhaps somewhat dimmed by the more striking splendor of the Regent which ere long was to attract all eyes and absorb all attention.