The six voyages of John Baptista Tavernier, Baron of Aubonne through Turky, into Persia and the East-Indies, for the space of forty years : giving an account of the present state of those countries, viz. of the religion, government, customs, and commerce of every country, and the figures, weight, and value of the money currant all over Asia : to which is added A new description of the Seraglio / made English by J.P. ; added likewise, A voyage into the Indies, &c. by an English traveller, never before printed ; publish'd by Dr. Daniel Cox

CHAP. XV. The Rule to know the just price and value of a Diamond of what weight soever, from three to a hunder'd, and upwards: a secret known to very few people in Europe.

I Make no mention of Diamonds of three Carats, the price thereof being suf∣ficiently known.

First then, as to others above that weight, you must know how much the Dia∣mond weighs, and see if it be perfect; if it be a thick Stone, well-squar'd, and have all its corners, if the water be white and lively, without specks and flaws. If it be a Stone cut in Facets, which we call a Rose-Diamond, you must take no∣tice whether the form be round or oval, whether it be of a fair breadth, and not of Stones clapt together; whether it be of a good water, and without specks or flaws.

Such a Stone weighing one Carat, is worth 150 Livres or more. Now to know how much a Stone of the same perfection, weighing 12 Carats, is worth.

Multiply 12 by 12, it makes 144. Then multiply 144 by 150, which is the price of a Stone of one Carat, it comes to 21600 Livres.

As for Example. 〈 math 〉〈 math 〉

To know the price of imperfect Diamonds, you must observe the same rule, grounded upon the price of a Stone of one Carat.

You have a Diamond of fifteen Carats shewn ye, neither of a good water, nor good form, and full of specks and flaws besides: such a Diamond cannot be worth above 60, or 80, or 100 Livres at most, according to the goodness of the Stone. Multiply therefore the weight of the Diamond of 15 Carats by 15: then multi∣ply the product, which is 125, by the value of the Stone of one Carat, which we will grant to be 80 Livres, the product whereof is 10000 Livres, the price of a Diamond of 15 Carats.

The Example. 〈 math 〉〈 math 〉

By that it is easy to discover the difference between a perfect and an imperfect Stone. For if that Stone of 15 Carats were perfect, the second multiplication should be wrought by 150, which is the price of a perfect Stone of one Carat: and then the Diamond would come not to 10000 Livres, but to 33750 Livres, that is 23750 Livres more than an imperfect Diamond of the same weight.

By this rule observe the price of two the greatest Diamonds of the World for Cut-stones, the one in Asia, belonging to the Great Mogul; the other in Europe, in the possession of the Duke of Tuscany.

The Great Mogul's Diamond weighs 279 and 9 16th Carats. It is of a perfect good water, of a good shape, with only a little flaw in the edg of the cutting be∣low, which goes round about the Stone. Without that flaw, the first Carat were worth 160 Livres, but for that reason I reckon it not at above 150; and so by the rule it comes to 11723278 Livres, 14 Sous, and 3 Liards. Did the Diamond weigh no more than 279 Carats, it would not be worth above 11676150 Livres, so that the nine 16ths comes to 47128 Livres, 14 Sous, and 3 Liards.

The Great Duke of Tuscany's Diamond weighs 139 Carats, clean and well∣shap'd, cut in facets every way: but in regard the water enclines somewhat to∣ward the colour of Citron, I do not value the first Carat above 135 Livres; so that by the rule the Diamond ought to be worth 2608335 Livres.

A Diamond by the Miners is call'd Iri, which the Turks, Persians and Arabians call Almas.