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US 12,317,970 B2Granted
Gemstone and methods of cutting the same
AssigneeAlbert Gad Ltd.
InventorReuven Paikin
Life of this patent
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Abstract
A gemstone includes a crown, a pavilion, and a girdle disposed between the crown and the pavilion. The girdle has a pear-shaped cross-section with a rounded end a tapered end narrower than the rounded end. The surface of the gemstone is generally divided into a number of groups of interlocking facets disposed at a variety of angles. The groups of facets comprising the surface of the crown generally include star facets, upper intermediate crown facets, lower intermediate crown facets, main crown facets, and upper girdle facets. The upper girdle facets generally abut an upper edge of the girdle. The groups of facets comprising the surface of the pavilion include culet-adjacent facets, candle facets, main pavilion facets, and lower girdle facets. The lower girdle facets generally abut a lower edge of the girdle.
Claims20
A method of forming a crown of a pear-shaped gemstone, comprising:
- forming a girdle defining a perimeter of the gemstone, the girdle having a pear-shaped cross-section, the pear-shaped cross section being an oval shape with a first rounded end and a second tapered end opposing the first rounded end, the second tapered end being narrower than the first rounded end;
- forming a first preliminary table on an upper portion of the gemstone, the first preliminary table defining a generally flat upper surface of the gemstone;
- forming a first temporary set of crown facets on the upper portion of the gemstone;
- forming a second temporary set of crown facets on the upper portion of the gemstone from a portion of the first preliminary table and a portion of each of the first temporary set of crown facets, such that the first preliminary table is reduced in size to form a second preliminary table and a remainder of the first temporary set of crown facets forms a third temporary set of crown facets;
- forming a fourth temporary set of crown facets on the upper portion of the gemstone from a portion of the second preliminary table and a portion of each of the second temporary set of crown facets, such that the second preliminary table is reduced in size to form a third preliminary table and a remainder of the second temporary set of crown facets forms a first final set of crown facets;
- forming a second final set of crown facets on the upper portion of the gemstone from a portion of each of the third temporary set of crown facets, such that a remainder of the third temporary set of crown facets forms a third final set of crown facets;
- and
- forming a fourth final set of crown facets on the upper portion of the gemstone from a portion of the third preliminary table and a portion of each of the fourth temporary set of crown facets, such that the third preliminary table is reduced in size to form a final table and a remainder of the fourth temporary set of crown facets forms a fifth final set of crown facets.
5 more elements
A method of forming a pavilion of a pear-shaped gemstone, comprising:
- forming a girdle defining a perimeter of the gemstone, the girdle having a pear-shaped cross-section, the pear-shaped cross section being an oval shape with a first rounded end and a second tapered end opposing the first rounded end, the second tapered end being narrower than the first rounded end;
- forming a first temporary set of pavilion facets on a lower portion of the gemstone;
- forming a second temporary set of pavilion facets on the lower portion of the gemstone from a portion of each of the first temporary set of pavilion facets, such that a remainder of the first temporary set of pavilion facets forms a third temporary set of pavilion facets;
- forming a fourth temporary set of pavilion facets on the lower portion of the gemstone from a portion of each of the second temporary set of pavilion facets and each of the third temporary set of pavilion facets, such that a remainder of the second temporary set of pavilion facets forms a first final set of pavilion facets and a remainder of the third temporary set of pavilion facets forms a fifth temporary set of pavilion facets;
- and
- forming a second final set of pavilion facets on the lower portion of the gemstone from a portion of each of the fourth temporary set of pavilion facets and a portion of each of the fifth temporary set of pavilion facets, such that a remainder of the fourth temporary set of pavilion facets forms a third final set of pavilion facets and a remainder of the fifth temporary set of pavilion facets forms a fourth final set of pavilion facets.
3 more elements
A method of forming a gemstone, the method comprising:
- forming a girdle defining a perimeter of the gemstone, the girdle having a pear-shaped cross-section, the pear-shaped cross section being an oval shape with a first rounded end and a second tapered end opposing the first rounded end, the second tapered end being narrower than the first rounded end;
- forming a first preliminary table on an upper portion of the gemstone, the first preliminary table defining a generally flat upper surface of the gemstone;
- forming a first temporary set of crown facets on the upper portion of the gemstone;
- forming a second temporary set of crown facets on the upper portion of the gemstone from a portion of the first preliminary table and a portion of each of the first temporary set of crown facets, such that the first preliminary table is reduced in size to form a second preliminary table and a remainder of the first temporary set of crown facets forms a third temporary set of crown facets;
- forming a fourth temporary set of crown facets on the upper portion of the gemstone from a portion of the second preliminary table and a portion of each of the second temporary set of crown facets, such that the second preliminary table is reduced in size to form a third preliminary table and a remainder of the second temporary set of crown facets forms a first final set of crown facets;
- forming a second final set of crown facets on the upper portion of the gemstone from a portion of each of the third temporary set of crown facets, such that a remainder of the third temporary set of crown facets forms a third final set of crown facets;
- forming a fourth final set of crown facets on the upper portion of the gemstone from a portion of the third preliminary table and a portion of each of the fourth temporary set of crown facets, such that the third preliminary table is reduced in size to form a final table and a remainder of the fourth temporary set of crown facets forms a fifth final set of crown facets;
- forming a first temporary set of pavilion facets on a lower portion of the gemstone;
- forming a second temporary set of pavilion facets on the lower portion of the gemstone from a portion of each of the first temporary set of pavilion facets, such that a remainder of the first temporary set of pavilion facets forms a third temporary set of pavilion facets;
- forming a fourth temporary set of pavilion facets on the lower portion of the gemstone from a portion of each of the second temporary set of pavilion facets and each of the third temporary set of pavilion facets, such that a remainder of the second temporary set of pavilion facets forms a first final set of pavilion facets and a remainder of the third temporary set of pavilion facets forms a fifth temporary set of pavilion facets;
- and
- forming a second final set of pavilion facets on the lower portion of the gemstone from a portion of each of the fourth temporary set of pavilion facets and a portion of each of the fifth temporary set of pavilion facets, such that a remainder of the fourth temporary set of pavilion facets forms a third final set of pavilion facets and a remainder of the fifth temporary set of pavilion facets forms a fourth final set of pavilion facets.
9 more elements
Dependencies are inferred from the claim text.