Precious and Semiprecious Stone Cut

Abstract

The present invention provides a cut stone including a top surface and a bottom surface and a girdle. The top surface includes a first facet row having 18 facets, a second facet row having 6 facets, and a third facet row having 6 facets. The bottom surface includes a first facet row having 18 facets, a second facet row having 6 facets, and a third facet row having 6 facets. The girdle is disposed between the first facet row of the top surface and the first facet row of the bottom surface.

1 . A cut gemstone, comprising:
 a top surface, including:
 a first facet row having 18 facets, 
 a second facet row having 6 facets, and 
 a third facet row having 6 facets; 
   a bottom surface, including:
 a first facet row having 18 facets, 
 a second facet row having 6 facets, and 
 a third facet row having 6 facets; and 
   a girdle disposed between the first facet row of the top surface and the first facet row of the bottom surface.   
   
   
       2 . The cut gemstone of  claim 1 , wherein the gemstone consists of 60 facets. 
   
   
       3 . The cut gemstone of  claim 2 , wherein the gemstone has a depth of about 46%. 
   
   
       4 . The cut gemstone of  claim 3 , wherein the first facet row forms an angle with respect to the horizontal of about 50°. 
   
   
       5 . The cut gemstone of  claim 4 , wherein the second facet row forms an angle with respect to the horizontal of about 15°. 
   
   
       6 . The cut gemstone of  claim 5 , wherein the third facet row forms an angle with respect to the horizontal between about 10°. 
   
   
       7 . The cut gemstone of  claim 2 , wherein the second facet row forms an angle with respect to the horizontal that is less than an angle formed by the first facet row, and the third facet row forms an angle with respect to the horizontal that is less than the angle formed by the second facet row. 
   
   
       8 . The cut gemstone of  claim 7 , wherein the gemstone has a depth of about 36% to 56%, the first facet row forms an angle with respect to the horizontal of about 38° to 50°, the second facet row forms an angle with respect to the horizontal of about 15° to 25°, and the third facet row forms an angle with respect to the horizontal of between about 5° to 25°. 
   
   
       9 . The cut gemstone of  claim 1 , wherein the top and bottom surfaces are dome-shaped, mirror images. 
   
   
       10 . The cut gemstone of  claim 1 , wherein the stone is selected from a group consisting of a precious stone, a semiprecious stone and a cubic zirconium. 
   
   
       11 . The cut gemstone of  claim 1 , wherein a shape of the stone is selected from the group consisting of round, pear, cushion, marquise and oval. 
   
   
       12 . The cut gemstone of  claim 1 , wherein the girdle is thin, very thin or extremely thin. 
   
   
       13 . The cut gemstone of  claim 1 , wherein the girdle is less than 0.6%. 
   
   
       14 . A jewelry piece comprising a cut gemstone mounted in a setting, the cut gemstone including:
 a top surface having a first facet row having 18 facets, a second facet row having 6 facets, and a third facet row having 6 facets;   a bottom surface having a first facet row having 18 facets, a second facet row having 6 facets, and a third facet row having 6 facets; and   a girdle disposed between the first facet row of the top surface and the first facet row of the bottom surface.   
   
   
       15 . The jewelry piece of  claim 14 , wherein:
 the gemstone consists of 60 facets,   the gemstone has a depth of between about 36% to 56%,   the first facet row forms an angle with respect to the horizontal of between 38° to 50°,   the second facet row forms an angle with respect to the horizontal smaller than the first facet row and between 15° to 25°, and   the third facet row forms an angle with respect to the horizontal smaller than the second facet row and between 5° to 25°.   
   
   
       16 . The jewelry piece of  claim 15 , wherein the setting includes a frame encircling the gemstone and at least two pairs of prongs. 
   
   
       17 . The jewelry piece of  claim 15 , wherein the setting is a prong setting, a bezel setting, a bar setting or a channel setting. 
   
   
       18 . The jewelry piece of  claim 15 , wherein the gemstone and the setting are incorporated into an earring, a necklace, a bracelet or a ring. 
   
   
       19 . A cut gemstone, comprising:
 a top surface, including:
 a first facet row having a primary number of facets, 
 a second facet row having a secondary number of facets less than the primary number of facets, and 
 a third facet row having the secondary number of facets; 
   a bottom surface, including:
 a first facet row having the primary number of facets, 
 a second facet row having the secondary number of facets, and 
 a third facet row having the secondary number of facets; and 
   a girdle disposed between the first facet row of the top surface and the first facet row of the bottom surface.   
   
   
       20 . The cut gemstone of  claim 19 , wherein the primary number is three times larger than the secondary number. 
   
   
       21 . The cut gemstone of  claim 20 , wherein the primary number is a multiple of 18 and the secondary number is a multiple of 6. 
   
   
       22 . A jewelry piece comprising the cut gemstone recited in  claim 19 .