| 主权项 |
1. A cut diamond having a plurality of facets, said cut diamond comprising:
a girdle portion having four sides and four corners, said girdle portion having a girdle plane; a crown portion adjacent to said girdle portion, said crown portion including:
a table facet having eight sides and eight vertices;four crown main facets, each of said four crown main facets positioned between said table facet and one of said four sides of said girdle portion, and extends between about one of said eight vertices of said table facet and about a midpoint of respective said one side, each of said four crown main facets being arranged at an angle between 38 and 42.5 degrees with respect to said girdle plane;four crown corner facets, each of said four crown corner facets positioned between said table facet and one of said four corners of said girdle portion, and extends between about one of said eight vertices of said table facet and about a midpoint of respective said one corner, each of said four crown corner facets further positioned between two of said four crown main facets, each of said four crown corner facets being arranged at an angle between 37 and 42.6 degrees with respect to said girdle plane;eight crown star facets, each of said eight crown star facets positioned between said table facet, one of said four crown main facets, and one of said four crown corner facets, each of said eight crown star facets being arranged at an angle between 28 and 36.5 degrees with respect to said girdle plane; andsixteen crown half facets, each of said sixteen crown half facets positioned between said girdle portion, one other said crown half facet, and one of one of said four crown main facets and one of said four crown corner facets, each of said sixteen crown half facets being arranged at an angle between 44.8 and 53.1 degrees with respect to said girdle plane; and a pavilion portion adjacent to said girdle portion and positioned diametrically opposite said crown portion, said pavilion portion tapering inward towards a point of convergence as it extends away from said girdle portion, said pavilion portion including:
four pavilion main facets, each of said four pavilion main facets positioned partially below one of said four crown main facets when said cut diamond is viewed from above, each of said four pavilion main facets further positioned between one of said four sides of said girdle portion and said point of convergence, and extends between about said midpoint of respective said one side and about said point of convergence, each of said four pavilion main facets being arranged at an angle between 39.3 and 41.9 degrees with respect to said girdle plane;four pavilion corner facets, each of said four pavilion corner facets positioned partially below one of said four crown corner facets when said cut diamond is viewed from above, each of said four pavilion corner facets further positioned between one of said four corners of said girdle portion and said point of convergence, and extends between about said midpoint of respective said one corner and about said point of convergence, each of said four pavilion corner facets being arranged at an angle between 35.5 and 40 degrees with respect to said girdle plane; andsixteen pavilion half facets, each of said sixteen pavilion half facets positioned between said girdle portion, one other said pavilion half facet, and one of one of said four pavilion main facets and one of said four pavilion corner facets, each of said sixteen pavilion half facets being arranged at an angle between 37 and 46.5 degrees with respect to said girdle plane, each of said sixteen pavilion half facets including a respective side extending from a respective girdle/pavilion point on said girdle portion towards said point of convergence with a respective pavilion half facet length that is less than or equal to about 85% of a respective total pavilion length from said respective girdle/pavilion point to said point of convergence, each of said respective pavilion half facet lengths and each of said respective total pavilion lengths measured along said girdle plane; wherein, when said cut diamond is viewed from above, a majority of said cut diamond reflects incident light impinging on said cut diamond at an angle between 45 and 75 degrees with respect to said girdle plane. |
