Improved shallow depth cut diamonds

Abstract

The invention is directed to shallow pavilion, cut diamonds having excellent optical characteristics. The shallow pavilion cut diamonds of the invention have a table with a table plane and a girdle. The cut diamonds have a shape and configuration that result in a specific total depth percentage, a specific crown height percentage, a specific girdle height percentage and a specific table percentage. A crown surface is located between the table and the girdle and extends in a crown angle to the table plane. A pavilion surface extends at a pavilion angle relative to the table. The pavilion surface includes a plurality of substantially planar main pavilion facets, each of which extend from the girdle to a pointed culet defining the bottom most portion of the cut diamond. The crown angle is in the range of between about 29 degrees to about 36 degrees, and the pavilion angle is in the range of between about 15 degrees and about 34.5 degrees. The shallow pavilion, cut diamonds of the invention may be either round shaped cut diamonds or fancy shaped cut diamonds.

We claim: 
     
         1 . A cut diamond having a round shape, the cut diamond comprising:
 a table having a table plane and a substantially annular girdle, the cut diamond having a shape and configuration that results in a specific total depth percentage, a specific crown height percentage, a specific girdle height percentage and a specific table percentage;   a crown surface located between the table and the substantially annular girdle and extending in a crown angle to the table plane;   a pointed culet defining the bottom most portion of the cut diamond;   at least three pavilion surfaces, each extending at a pavilion angle relative to the table plane;   and, wherein the crown angle is in the range of 29 degrees to 36 degrees and the pavilion angle is in the range of 25 degrees and 36 degrees.   
     
     
         2 . The round cut diamond of  claim 1  wherein the total depth percentage is in the range of 25 percent to 50 percent. 
     
     
         3 . The round cut diamond of  claim 1  wherein the table diameter is in the range of 55 percent to 85 percent. 
     
     
         4 . The round cut diamond of  claim 1  wherein the crown height is in the range of 7 percent to 15 percent. 
     
     
         5 . The round cut diamond of  claim 2  wherein the total depth percentage is in the range of 35 percent to 47 percent. 
     
     
         6 . The round cut diamond of  claim 3  wherein the table diameter is in the range of 66.5 percent to 85 percent. 
     
     
         7 . The round cut diamond of  claim 4  wherein the crown height is in the range of 9 percent to 12 percent. 
     
     
         8 . The round cut diamond of  claim 1  wherein the pavilion angle is in the range of 30 degrees to 33 degrees. 
     
     
         9 . A fancy cut diamond comprising:
 a table having a table plane and having a non-circular circumference girdle, the cut diamond having a shape and configuration that results in a specific total depth percentage, a specific crown height percentage, a specific girdle height percentage and a specific table percentage;   a crown surface located between the table and the girdle having a non-circular circumference and extending in a crown angle to the table plane;   at least three pavilion surfaces, each extending at a pavilion angle relative to the table, the pavilion surfaces include a plurality of substantially planar main pavilion facets, each of the plurality of substantially planar main pavilion facets extend from the girdle having a non-circular circumference to a pointed culet defining the bottom most portion of the cut diamond; and,   wherein the crown angle is in the range of 29 degrees to 36 degrees and the pavilion angle is in the range of 15 degrees and 34.5 degrees.   
     
     
         10 . The fancy cut diamond of  claim 9  wherein the pavilion angle is in the range of 22 degrees to about 33 degrees. 
     
     
         11 . The fancy cut diamond of  claim 9  wherein the table diameter is in the range of 60 percent to about 85 percent. 
     
     
         12 . The fancy cut diamond of  claim 9  wherein the diamond has a pear shape. 
     
     
         13 . The cut diamond of  claim 9  wherein the diamond has a cushion shape. 
     
     
         14 . The fancy cut diamond of  claim 9  wherein the diamond has a heart shape. 
     
     
         15 . A cut diamond comprising:
 a table having a table plane and a girdle, the cut diamond having a shape and configuration that results in a specific total depth percentage, a specific crown height percentage, a specific girdle height percentage and a specific table percentage;   a crown surface located between the table and the girdle and extending in a crown angle to the table plane;   at least four pavilion surfaces, each extending at a pavilion angle relative to the table, the pavilion surfaces includes a plurality of substantially planar main pavilion facets, each of the plurality of substantially planar main pavilion facets extend from the girdle to a pointed culet defining the bottom most portion of the cut diamond; and,   wherein the crown angle is in the range of 29 degrees to 36 degrees and the pavilion angle is in the range of 15 degrees and 34.5 degrees.   
     
     
         16 . The cut diamond of  claim 15  wherein the total depth is in the range of 25 percent to 55 percent. 
     
     
         17 . The cut diamond of  claim 15  wherein the table percentage is in the range of 50 percent to 90 percent. 
     
     
         18 . The cut diamond of  claim 15  wherein the crown height is in the range of 7 percent to 15 percent. 
     
     
         19 . The cut diamond of  claim 15  wherein the pavilion angle is in the range of 22 degrees and about 33 degrees. 
     
     
         20 . The cut diamond of  claim 15  wherein the diamond has a round shape. 
     
     
         21 . The cut diamond of  claim 15  wherein the diamond has an oval shape.