Page:Philosophical Transactions - Volume 002.djvu/28

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An Account

Of a small Book in French, entituled

HISTOIRE DES JOYAUX.

ET

Des Principales Richesses de l' Orient et de l' Occident,

par le Sr. Chapuzeau.

This History treats of Diamonds, Rubies, Emeraulds, Pearls, Coral, Bezoar, Yellow Amber, Amber-gris, Indigo, &c.

Of Diamonds, The Author shews:

1. The Places, whence they are taken; of which he finds but Five in all the East-Indies, whereof two are Rivers, vid. Saccadan in Borneo, and Nage in the Kingdom of Bengala; at the bottom of both which, he saith, the Diamonds are found among the sand, after the waters, that fall as great Torrents from the Mountains, are run off; and the three others are Mines, in the Kingdoms of Decan, Cuncan, and Golconda. In this Relation he observes, that the Diamonds which are found at the bottom of those Rivers, have the best Water; but those, in Mines, have often Flaws (which he imputes to the violent knockings of the Rock) and Blebs, ascribed to the condition of the Earth or Sand they are found in, vid. when that is not pure, but fattish or black. He takes also notice, that Diamonds are the heaviest of precious Stones, as Gold is of Mettals.

2. The Manner, how they are found and separated; which is the same in substance, with that, described Num 18, p. 328.

3. The Price of them, according to the proportion of their weight; for which he gives this Rule. Take, saith he, a Diamond of 10 Carats: this number is to be squared (which makes 100.) then, if the Stone be clean, each Carat according to its perfection, may be worth 40 to 60 Crowns; if it have no good water, or have a Bleb or Flaw, the Carat will not be worth but from 10 to 30 Crowns, So multiplying the said l00 by the number, which each Carat of such or such a Stone may be worth, the product is the price of the Stone.

For