Diamonds and precious stones, a popular account of gems .. . Fig. 109.—Holland Rose. Sometimes rough diamonds, found in the formof pears, are covered with little facets, retainingthe general form. These stones have the name ofbriolettes; they come exclusively from India, and aregenerally pierced in the upper part with a verysmall hole. No lapidary in Europe could drillsuch a hole in these diamonds. There are also known in commerce stones cut DIAMOND-CUTTING. 263 into pendeloques or pendants, in the form of a half-pear with table and collet, covered with facets onthe collet side. They are very
Diamonds and precious stones, a popular account of gems .. . Fig. 109.—Holland Rose. Sometimes rough diamonds, found in the formof pears, are covered with little facets, retainingthe general form. These stones have the name ofbriolettes; they come exclusively from India, and aregenerally pierced in the upper part with a verysmall hole. No lapidary in Europe could drillsuch a hole in these diamonds. There are also known in commerce stones cut DIAMOND-CUTTING. 263 into pendeloques or pendants, in the form of a half-pear with table and collet, covered with facets onthe collet side. They are very rare, and theirprice far exceeds that of brilliants of the sameweight. Fig. 110 represents one of the pendeloqueswhich Tavernier saw in India, and which its pos-sessor would not part with for $11,160. Another special form of cutting is that which wasemployed for *the Sancy. Diamonds cut in this. Fig. no.—Pendeloque of Tavernier. style have the form of flattened pears almost round,of a pendeloque shape, facetted both superiorly andinferiorly, and having a very small table Babinet thinks that this is the form in whichboth the Koh-i-noor and the Star of the Southshould have been cut. There is also the Star, invented by Caire, andbut little used. It was designed in order to take 264 PRECIOUS STONES. advantage of certain clear portions of rough dia-monds, which could not be otherwise used with-out great sacrifice of material. Fig. m will showthe appearance of stones cut in this manner. Theform on the left represents the upper portionof the stone; the other two figures are alterna-tive forms in which the lower portion of the stonemay be cut. The cutting of the diamond includes three series*of operations: the splitting or cleaving\ the cutting,
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectgems, booksubjectprec
