Diamonds and precious stones, a popular account of gems .. . Fig. 106. Fig. 107. These are the proportions in which the axis iscut by the French lapidaries, but English lapidariesusually cut five-eighteenths from the upper pyra-mid, and one-eighteenth from the lower. Theupper and larger plane surface is called the table;the lower is named the collet (French, culasse). The four superior edges or ribs, and the four in-ferior edges, are then removed in such a way thatthe table and the collet are circumscribed by regularoctagons, as represented by Fig. 105. DIAMOND-CUTTING. 261 Lastly, the eight f
Diamonds and precious stones, a popular account of gems .. . Fig. 106. Fig. 107. These are the proportions in which the axis iscut by the French lapidaries, but English lapidariesusually cut five-eighteenths from the upper pyra-mid, and one-eighteenth from the lower. Theupper and larger plane surface is called the table;the lower is named the collet (French, culasse). The four superior edges or ribs, and the four in-ferior edges, are then removed in such a way thatthe table and the collet are circumscribed by regularoctagons, as represented by Fig. 105. DIAMOND-CUTTING. 261 Lastly, the eight faces which Hmit the table arecut each into four facets, forming the crown; andthe eight faces of the collet are divided in the samemanner to obtain the pavilion. The stone bears then sixty-four facets, besidesthe two parallel planes—the table and the is called the double-cut, or reçut brilliant, andbeing the style which best displays all the beautiesof the diamond, it is used at the present day for allstones of fine water and of sufficient dep
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectgems, booksubjectprec
