Patent ID: 7192337
Filing Date: 2007-03-20
Classification: A44C

Abstract:
1. A method for cutting a diamond having a girdle, a crown formed on an upper side of the girdle and provided with a table at an upper portion thereof, and a pavilion formed on a lower side of the girdle, said method comprising: defining a first reference line on said table; defining a second reference line on said table, said second reference line crossing said first reference at a right angle so as to define four sectors; defining third reference lines on said table, said third reference lines intersecting said first reference line and said second reference line at a central point of said table so as to divide each of said four sectors into four equal sub-sectors; defining a first arc-connected line on said table, said first arc-connected line having a diameter equal to a diameter of said table and intersecting said first reference line, said second reference line and said third reference lines at first points such that a chord is defined by every two immediately circumferentially adjacent ones of said first points, whereby defined by said chords is a 16-cornered right polygonal shape; defining a second arc-connected line on said crown, said second arc-connected line having a diameter greater than said diameter of said first arc-connected line and being centrally co-axial with said first arc-connected line; defining a third arc-connected line that corresponds to an outer circumference of said girdle, said third arc-connected line having a diameter greater than said diameter of said second arc-connected line and being centrally co-axial with said second arc-connected line; defining fourth reference lines on said crown, said fourth reference lines defining first line segments extending from every two immediately circumferentially adjacent ones of said first points to one of said second points that corresponds to an intersection of said second arc-connected line and a corresponding one of said fourth reference lines that bisects said chord defined by said every two immediately circumferentially adjacent ones of said first points, so as to define a first planar portion by said first line segments and said chord; defining fifth reference lines on said crown, said fifth reference lines defining second line segments from every two immediately circumferentially adjacent ones of said second points to one of said fifth points that corresponds to an intersection of said third arc-connected line and a corresponding one of said fifth reference lines that passes between said every two immediately circumferentially adjacent ones of said second points, so as to define cutting said diamond along said first planar portions to form star facets, cutting said diamond along said second planar portions to form upper main facets, and cutting said diamond along said paired third planar portions to form paired upper girdle facets.