Abstract: To provide a diamond rendering reflective light off a table goldenly brilliant by making a proportion thereof symmetrical at any place viewed from an upper face, a side face or a bottom face, a first reference line, a second reference line crossing the first reference lines at a right angle and third reference lines equally dividing segments defined by an intersection of the first reference line and the second reference line into four equal parts, respectively, are provided. A first arc line intersects these reference lines. An approximately regular hexadecagon shaped table is established by line segments defined between these first intersections of the reference lines with the first arc line. Fourth reference lines dividing sectors defined between the third reference lines into two equal parts and a second arc line concentric with and larger than the first arc line, are provided.

Abstract: To provide a diamond rendering reflective light off the table goldenly brilliant by making a proportion thereof symmetry at any place viewed from an upper face, a side face or a bottom face, first reference lines, second reference lines crossing the first reference lines at right angles and third reference lines equally dividing the first reference lines and the second reference lines into four equal parts, respectively are provided. A first arc line is made by intersections of the reference lines. The approximately regular hexadecagon shaped table is established by connection of the intersections of the reference lines with the first arc line. Fourth reference lines dividing the third reference lines into two equal parts and a second arc line with a circle concentric with and larger than the first arc line is made. Star facets are established by connection of the intersections among the fourth reference lines and the second arc line with the top of the table.

Abstract: To provide a diamond rendering reflective light off the table goldenly brilliant by making a proportion thereof symmetry at any place viewed from an upper face, a side face or a bottom face, first reference lines, second reference lines crossing the first reference lines at right angles and third reference lines equally dividing the first reference lines and the second reference lines into four equal parts, respectively are provided. A first arc line is made by intersections of the reference lines. The approximately regular hexadecagon shaped table is established by connection of the intersections of the reference lines with the first arc line. Fourth reference lines dividing the third reference lines into two equal parts and a second arc line with a circle concentric with and larger than the first arc line is made. Star facets are established by connection of the intersections among the fourth reference lines and the second arc line with the top of the table.

Abstract: Disclosed is a diamond cutting method comprising the steps of: forming a square or rectangular table in a piece of gemstone; and forming a pavilion continuous to the table by cutting vertically from each side of the square or rectangular table to define the four lower-girdle facets and by cutting obliquely from each corner of the square or rectangular table to the culet of the pavilion to form four lower-main facets, whereby the upper opposite sides of each lower-main facet adjoining the adjacent lower-girdle facets whereas the lower opposite sides of each lower-main facet adjoining the confronting lower opposite sides of the adjacent lower-main facets. An enneahedral-cut diamond thus produced is a table-and-pavilion structure, permitting plural diamonds to be arranged side by side as a whole with their square or rectangular tables directed inward or outward.

Abstract: Disclosed is a diamond cutting method comprising the steps of: forming a square or rectangular table in a piece of gemstone; and forming a pavilion continuous to the table by cutting vertically from each side of the square or rectangular table to define the four lower-girdle facets and by cutting obliquely from each corner of the square or rectangular table to the culet of the pavilion to form four lower-main facets, whereby the upper opposite sides of each lower-main facet adjoining the adjacent lower-girdle facets whereas the lower opposite sides of each lower-main facet adjoining the confronting lower opposite sides of the adjacent lower-main facets. An enneahedral-cut diamond thus produced is a table-and-pavilion structure, permitting plural diamonds to be arranged side by side as a whole with their square or rectangular tables directed inward or outward.

Abstract: Disclosed is a diamond cutting method comprising the steps of: forming a square or rectangular table in a piece of gemstone; and forming a pavilion continuous to the table by cutting vertically from each side of the square or rectangular table to define the four lower-girdle facets and by cutting obliquely from each corner of the square or rectangular table to the culet of the pavilion to form four lower-main facets, whereby the upper opposite sides of each lower-main facet adjoining the adjacent lower-girdle facets whereas the lower opposite sides of each lower-main facet adjoining the confronting lower opposite sides of the adjacent lower-main facets. An enneahedral-cut diamond thus produced is a table-and-pavilion structure, permitting plural diamonds to be arranged side by side as a whole with their square or rectangular tables directed inward or outward.

Abstract: Disclosed are a new diamond cutting method and a diamond shape or proportion giving an increased brightness and different brilliant colors to the cut jewel. A piece of diamond having a crown or bezel and a pavilion converging up and down from its girdle is prepared; the table of the crown is cut into a regular polygon having straight sides of an integer multiple of three; star facets, upper-main facets and paired upper-girdle facets are formed on the oblique annular surface between the polygonal table and the girdle; and lower-girdle facets and lower-main facets are cut on the pavilion. The height of the diamond piece is approximately 64% of the diameter of the girdle; the height of the crown is approximately 15.7%; the height of the pavilion is approximately 48.3%; and the largest width of the girdle is approximately 1.2 to 1.4%. The angle formed between the ridge of the crown and the ridge of the pavilion is approximately 77 degrees.

Abstract: Disclosed is a diamond cutting method comprising the steps of: forming a square or rectangular table in a piece of gemstone; and forming a pavilion continuous to the table by cutting vertically from each side of the square or rectangular table to define the four lower-girdle facets and by cutting obliquely from each corner of the square or rectangular table to the culet of the pavilion to form four lower-main facets, whereby the upper opposite sides of each lower-main facet adjoining the adjacent lower-girdle facets whereas the lower opposite sides of each lower-main facet adjoining the confronting lower opposite sides of the adjacent lower-main facets. An enneahedral-cut diamond thus produced is a table-and-pavilion structure, permitting plural diamonds to be arranged side by side as a whole with their square or rectangular tables directed inward or outward.

Abstract: Disclosed are a new diamond cutting method and a diamond shape or proportion giving an increased brightness and different brilliant colors to the cut jewel. A piece of diamond having a crown or bezel and a pavilion converging up and down from its girdle is prepared; the table of the crown is cut into a regular polygon having straight sides of an integer multiple of three; star facets, upper-main facets and paired upper-girdle facets are formed on the oblique annular surface between the polygonal table and the girdle; and lower-girdle facets and lower-main facets are cut on the pavilion. The height of the diamond piece is approximately 64% of the diameter of the girdle; the height of the crown is approximately 15.7%; the height of the pavilion is approximately 48.3%; and the largest width of the girdle is approximately 1.2 to 1.4%. The angle formed between the ridge of the crown and the ridge of the pavilion is approximately 77 degrees.

Abstract: Disclosed are a new diamond cutting method and a diamond shape or proportion giving an increased brightness and different brilliant colors to the cut jewel. A piece of diamond having a crown or bezel and a pavilion converging up and down from its girdle is prepared; the table of the crown is cut into a regular polygon having straight sides of an integer multiple of three; star facets, upper-main facets and paired upper-girdle facets are formed on the oblique annular surface between the polygonal table and the girdle; and lower-girdle facets and lower-main facets are cut on the pavilion. The height of the diamond piece is approximately 64% of the diameter of the girdle; the height of the crown is approximately 15.7%; the height of the pavilion is approximately 48.3%; and the largest width of the girdle is approximately 1.2 to 1.4%. The angle formed between the ridge of the crown and the ridge of the pavilion is approximately 77 degrees.