GETTING UNDER THE SKIN OF THE DIAMOND

Evening Post, Volume CXXIV, Issue 57, 4 September 1937, Page 27

GETTING UNDER THE SKIN OF THE DIAMOND

We are buying more diamonds (says a writer in the '-'Daily Express"). "Last year,, sales totalled £8,500,000,? says the chairman pf De Beers, "and I see no reason why they should npt ex* ceed £10,000,000 this year."'

In ancient times the diamond Was almost unknown; the Persians in the thirteenth century considered pearl, ruby, and emerald to be of greater value; the Middle Ages placed it below emerald and ruby. Owing to the presence of %v. outer skin, diampnds, when first found, often have the appearance, of: a piece of washing soda, and up to. the. fifteenth century all feat was d.on,e. was to remove this dull skin and perish up. the natural faces, . r ■ In 1475 a French lapidary, Lpuis de Berquem, discovered feat by rubbing diamonds hard together they ground each pfeer. Bequem had had. m hi?, keeping three l%rg(e. diamond* belong* ing to Chiles the Bold, and Wife these he 3uda.ci.QUs.ly e^erimented, The results so delighted them, both that he experimented further,, and. in-, vented the vise of wheel? covered with, diamond dust for grinding purposes. At almost the same time lapidaries in India also discovered the. properties of diamond dust, _ ■ , For nearly three centuries after this the only shapes cut were the diamondpoint (eight facets) and the diamond table (twelve facets). The close of another century introduced the fa,n>* pus Rose-pattern-^-twentyT.four tin* angular facets on a flat base. About 180 ft a Venetian, Vinceni^q Perruzzi, revolutionised diam,Qn,d cut-. ting by introducing the '-'brilliant" cyt -^the standard style that-exists, todaySo superior is the "brilliant' pver all other cuttings* so, great fee added, fire

[and scintillation,, that many stonea of other shape hj<ve been, recut as brilliants, even a.Vfee, Sacrifice of weight. In a perfeot feriffiwt; there are fiftyeighi; facets;; Ih,»rty'th«e.a.bovo- and twenty-five helpw tM girdle, .1-o.,fee edge separating fee top and. bottom halves .of the out stpni, She actual 'topis a table facet, fee, *>°*teffli» toy flat "facet, called the <?u.let. fhough fifty-eight is. the gtaßdWd number of facets, large stonea are often cut into sixty-six; the largest. brilliant cut ftom the famoivs Ci}llin.an diamond U Mioue in having seventar-four,. t tt , .. ■ In ad.ditiQft tQ fee «briJU«\t/' fef shape TOpst popular today is* Vm known as the Erhmld., or ftofflte'.W some fire is sacrificed^- fe'OWlk having an. "e^tipsJsirg^ i^WeSmjilldiamond* m> m\ M, &$& shape* auc.h as battle, h,aU,rAopii, lozenge, tjap^e,p W t«K«i and baton, , mitfit tp, fee -tuMamA m* to m own powder. By an old method still in use, caUed fewtina, t(f^°* similar size ar? flfflOy flx«d tp two holdm m& rubbed hard together uijtil face**?* thimMifed aSfa are dev^oped in e^ohftOn.^t^ #mQ!>A P^der so caused being wviJlW in ft tray below the "holder?, fhp stpne* ar« R%xt passed to a polisher, who work* the facets. w . V a. i»or« r?g«lw }h.%pe and polishes them- The various facets are known as ite table, fee templets, the pavilions, the quoins, the small facets, and the culet. 'fod*? h&»dbruting has been largely superseded by machine. . • - . . . The cost of cutting diamonds is governed by the weight of the original material, and varies from 25s to 40a a carat on the original mass, or 75» to 120s if calculated on the finished gems. A carat is 150 th, PMt pf an pu.nee,.