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Ch. 5: Gem History Properties

Ch. 5: Gem History Properties Page of 515 Ch. 5: Gem History Properties Text size:minus plus Restore normal size   Mail page  Print this page
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flaws, if any, shall have been taken out. So great a stress is laid, by modern fashion, on the superficial extent of a brilliant, that the old rules of proportioning its dimensions are now nearly obsolete: the best Cutters have entirely discarded the use of measures, and, in forming the facets, trust wholly to an accurate and well-practised eye. The direction being determined on, the artist must he well aware which are the hard points and which the soft ones • the former being those solid angles of the original octahe-dron, which it is necessary to cut directly across, and the latter those solid angles which are to be obliquely divided. A degree of force which may be safely applied, and is even requisite in making a section through the former, will be very apt to flaw and tear up the laminae when applied to latter. On these accounts it probably is, that the fatiguing and even painful process of performing this part of the business by hand, is not yet superseded by the use of machinery.
" These preliminary matters' being settled, the diamond is imbedded ina strong cement, fixed at the end of a stout spindle-shaped stick, about a foot long, with that portion only projecting, the removal of which is to form the first facet. The instrument employed for this purpose is another diamond, fixed in a stick similar to the former, with one of the solid angles projecting. In order to collect the powder and shivers that are detached during the process, the cut­ting is performed over a strong box, four or five inches square, furnished with a false bottom perforated with ex cessively minute holes, in order to sift, as it were, the dust from the shivers; and also with two upright iron pegs, fixed on the sides, for the workman to support and steady his fingers against, while with a short repeated stroke, somewhat between scratching and cutting, he is splitting off, or more laboriously wearing away the diamond in that
Ch. 5: Gem History Properties Page of 515 Ch. 5: Gem History Properties
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