1306854 Gems J HUISMAN and H HUISMAN 27 May 1970 [10 June 1969] 25497/70 Heading A3H [Also in Division B3] A process for cutting a diamond to have seventy-two facets in its pavilion side (excluding the culet facet 10) is to divide the pavilion into four equal facets which are then bifurcated to form eight triangular facets. These facets are then each trifurcated so that in each trio one facet is culet-adjoining while the remaining two facets 18 are girdle-adjoining. The girdle 15 is now polished to a 90‹ edge and further facets 30 are cut at each intersection of the girdle-adjoining facets 18. Triangular facets 40 are cut into these further facets and the girdle 15 is cut into a total of thirty-eight facets The finished gem is the subject of Specification 1094140. In a modification, the facets 30 are each further subdivided into two equal triangular facets to yield a gem with 88 facets in the pavilion side.
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