CN111053340A

CN111053340A - Twelve-butterfly diamond and processing method thereof

Info

Publication number: CN111053340A
Application number: CN201911297564.5A
Authority: CN
Inventors: 李金华
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-12-17
Filing date: 2019-12-17
Publication date: 2020-04-24
Anticipated expiration: 2039-12-17
Also published as: CN111053340B

Abstract

The invention discloses a twelve-butterfly one-flower diamond and a processing method thereof, relates to the field of jewelry, and particularly relates to a diamond with twelve butterflies one-flower inside and a processing method thereof. For the diamond, people want to have a diamond which can present a butterfly shape and a flower shape in the diamond without destroying the conical shape of the diamond. A twelve-butterfly diamond comprising: the multifunctional kite comprises a table top, twelve triangular kite surfaces, twelve main crown surfaces, twelve first upper-waist triangular surfaces, twelve second upper-waist triangular surfaces, twenty-four first sole surfaces and twelve second sole rake surfaces. The special magnifier is attractive when being observed under a special magnifier, and the beauty of twelve butterflies inside the special magnifier dancing around a flower can be observed, so that the sparkling effect of the diamonds is improved by 5-10%.

Description

Twelve-butterfly diamond and processing method thereof

Technical Field

The invention relates to the field of jewelry, in particular to a diamond with twelve butterflies inside and a processing method thereof.

Background

Diamond parts:

diamond CROWN (CROWN): the upper part of the diamond, called the crown, comprises 1 TABLE (TABLE), 8 star facets (STARFACET), 8 kite facets (bezaficet) and 16 upper waist facets (UPPERGIRDLEFACET), for a total of 33 facets.

Waist circumference (GIRDLE): the widest part of the diamond is also the junction of the crown part on the upper surface of the diamond and the pavilion part under the diamond, and the waistline is the part for fixing the diamond when the jewel is inlaid.

The part under the PAVILION (PAVILION) diamond is called PAVILION, that is, the part from below the waist to the diamond tip. Comprises 16 waist planes (LOWERGERDLEFACET), 8 pavilion facets (PAVILIONFACET) and 1 bottommost base plane (CULET), and 25 facets in total; because the diamond does not necessarily have a pavilion with no pavilion, it has only 24 facets, and the total number of facets is 57.

For diamonds with the same size and cleanliness, in addition to the classic processing technique of the diamond, the cutting technique of the diamond is gradually marked by a unique cutting mode among brands. In pursuit of different sparkle types, different cutting styles present diamonds with different sparkle degrees, either more sparkling, such as brilliant, or more convergent, such as square, which look at the individual's orientation.

Two steps are essential for any diamond blank, namely 'scribing', 'valving and polishing'. The position and angle of the petals generated by a finely cut diamond are accurately calculated to maximize the brilliance of the diamond. It follows that cutting the hardest gemstone in the world, diamond, requires not only advanced equipment, but also a great deal of experience, high degree of responsibility and attention from the cutting engineer to release the full potential beauty of the diamond.

Standard round bright formula (standardroundbright):

the most common forms on the market include: 1 mesa, 8 kite facet, 8 star facet, 16 waist up facet, 16 waist down facet, 8 bottom main facet, and one sharp facet, which may or may not be present, for a total of 57 or 58 facets. Figure 1 clearly shows the specific location of the above facets of the diamond. Generally, a diamond of less than 5 carats has no point, so that the point of the Culet point on the certificate is None or Verysmall, etc., i.e. the point is None or negligibly small, i.e. 57 faces. In order to protect the diamond from damage, the large-particle diamond is generally flattened, so that one more surface, namely 58 surfaces, is provided. Many people often believe that the more facets a diamond is the better, and this is not true, and many types of gemstones are carved, especially shaped diamonds, which can extend over many facets, not all of which are the more facets the better. As a round drill, standard brilliant cuts (57-58 facets), also a classical lathe, are a very classic and perfect way of cutting.

Patent No. CN201811163063.3 entitled invention patent of diamond structure, discloses that the crown part 1 comprises 1 table top (11) on the top surface, the table top (11) is an undecamornate, each vertex of the table top (11) is provided with a hexagonal crown main surface (13) in the direction towards the waist (3), one vertex of the crown main surface (13) is located on the waist (3), the vertex of the crown main surface (13) on the table top (11) and the vertex on the waist (3) are two symmetrical points of the hexagonal crown main surface (13), and two adjacent crown main surfaces (13) share one edge; the pavilion (2) comprises 11 pavilion main surfaces (22) sharing vertexes, the pavilion main surfaces (22) are quadrilateral, one vertex of each pavilion main surface (22) is positioned on the waist part (3), and two adjacent pavilion main surfaces (22) share one side. The patent adopts an accurate cutting process and a facet design of a crown part, so that the diamond forms a rose shape under the irradiation of light; the crown part and the pavilion part can see rose light shadows under the overlooking condition through special angle design, eleven planar rose light shadows are formed at three main light angles appearing at the joint of two adjacent crown main surfaces, the aesthetic feeling of the diamond is improved, and the using effect and the using benefit of the diamond structure are effectively guaranteed.

Jewellery is the pursuit of lovers 'elements in love, while butterflies are lovers' loyalty, have only one partner in a lifetime, and are one of the representatives of insect world faithfulness, and butterflies are regarded as the symbol of good luck and beauty by people, such as butterflies loving flowers are often used for sweet love and happy marriage, and the pursuit of mankind to being good at beauty is expressed. For the diamond, people want to have a diamond which can show a butterfly shape and a flower shape inside the diamond without damaging the conical shape of the diamond, and the diamond is combined together, so that the moral is more beautiful, and the scene is beautiful and unreasonable, so that new varieties of butterfly diamond series are increased.

However, as the restriction of the traditional diamond polishing process is applied, no new variety of butterfly diamond series is added up to now; in addition, the sparkling effect of the traditional diamond is further improved.

Disclosure of Invention

In order to make the interior of the diamond present a pattern that twelve butterflies surround a flower and improve the sparkling effect of the diamond, a twelve butterflies diamond and a processing method thereof are provided.

A twelve-butterfly diamond comprising: the table comprises a table top 1, twelve triangular kite surfaces 13, twelve main crown surfaces 12, twelve first upper waist triangular surfaces 14, twelve second upper waist triangular surfaces 15, twenty-four first bottom foot surfaces 3 and twelve second bottom rake tip surfaces 31, wherein the second bottom rake tip surfaces 31 are rhombic; the length h1 of the second bottom rake tip surface 31 accounts for 20-50% of the distance from the bottom rake tip 301 to the waist.

A one-flower twelve-butterfly diamond comprises a table board 1, twelve triangular kite surfaces 13, twelve main crown surfaces 12, twelve first upper waist triangular surfaces 14, twelve second upper waist triangular surfaces 15, twenty-four first bottom foot surfaces 3 and twelve second bottom pick-up tip surfaces 31, wherein the second bottom pick-up tip surfaces 31 are rhombic, the first bottom foot surfaces 3 and the waist reference surface are in a first included angle α value range of 41.5-42.5 degrees, and the second bottom pick-up tip surfaces 31 and the waist reference surface are in a second included angle β value range of 35-39 degrees.

A one-flower twelve-butterfly diamond comprises a table board 1, twelve triangular kite surfaces 13, twelve main crown surfaces 12, twelve first upper waist triangular surfaces 14, twelve second upper waist triangular surfaces 15, twenty-four first bottom foot surfaces 3 and twelve second bottom pick-up tip surfaces 31, and is characterized in that the length h1 of each second bottom pick-up tip surface 31 accounts for 20% -50% of the distance from a bottom tip 301 to the waist, the first bottom foot surfaces 3 and the waist reference surface are a first included angle α with the range of 41.5-42.5 degrees, and the second bottom pick-up tip surfaces 31 and the waist reference surface are a second included angle β with the range of 35-39 degrees.

In the diamond, the main crown surface 12 and the waist reference surface form a third included angle gamma, and the value range of gamma is 32-38 degrees; the triangular kite surface 13 and the waist reference surface form a fourth included angle omega, the value range of omega is 28-33 degrees, or the height h2 of the upper waist triangular surface accounts for 50% -70% of the distance from the waist to the table board 1; the first upper waist triangular surface 14 and the second upper waist triangular surface 15 form a fifth included angle phi with the waist reference surface, and the value range of phi is 40-44 degrees.

A method for processing twelve butterfly diamonds in one flower comprises the following steps:

1, cutting a table board 1, and cutting a large plane on a drill blank to be used as the table board 1;

2, cutting the waist, and polishing the waist on the drill blank;

3, cutting the pavilion, and processing the part below the waist on the drilling blank into a bottom part which is approximately conical;

4, processing a crown part, namely processing the part above the waist part on a drilling blank into a crown part similar to a frustum shape;

the step 3 comprises the following steps:

3.1 taking the plane of the waist as a reference plane, wherein the reference plane is parallel to the plane of the table board 1, twenty-four first bottom foot surfaces 3 are ground towards the middle lower part of the waist at a first included angle α, the twenty-four first bottom foot surfaces 3 are intersected at a rake point 301, and the twenty-four first bottom foot surfaces 3 form a twenty-fourteen pyramid;

3.2 based on the intersected ridge 302 of two adjacent first sole surfaces 3, polishing a first quadrilateral second sole rake surface 31 to two sides of the ridge 302 or according to a first preset length h1 by using a second included angle β with the rake tip point 301 as a starting point, and then polishing twenty-four first sole surfaces 3 into twelve second sole rake surfaces 31 according to the same method, wherein the angle of the second included angle β is smaller than that of the first included angle α;

the step 4 comprises the following steps:

4.1, grinding the crown part into a regular dodecagonal table surface 1 and twelve main crown surfaces 12 by aligning a second bottom rake sharp surface 31 of the pavilion part at a third included angle gamma;

4.2 on the basis of 4.1, grinding a first triangular kite surface 13 by using a fourth included angle omega or according to a second preset length h2 with the table top 1 as a starting point on the basis of an edge intersected by two adjacent main crown surfaces 12; two end points 102 of the triangular kite surface 13 on the table top 1 are positioned at the middle point of the intersection line of the main crown surface 12 and the table top 1;

4.3, grinding twelve triangular kite surfaces 13 by a method of grinding a first triangular kite surface 13;

4.4 based on the rest section of the ridge 101 of the main crown surface 12, polishing a first upper lumbar triangular surface 14 towards the center direction of the main crown surface 12 by taking the intersection point 103 of the ridge 101 intersected by the two main crown surfaces 12 on the lumbar circle as a starting point and a fifth included angle phi;

4.5 grinding a second upper lumbar triangular surface 15 symmetrical to the first upper lumbar triangular surface 14 towards the center direction of the other main crown surface 12 by taking the ridge 101 of the primary crown surface 12 which is not ground in two adjacent main crown surfaces 12 in 4.4 as a symmetrical axis and taking the intersection point 103 of the ridge 101 on the waist circle as a starting point on the basis of 4.4;

4.6 two symmetrical first upper waist triangular surfaces 14 and second upper waist triangular surfaces 15 are called a pair of upper waist triangular surfaces 16;

4.7 polishing a second pair of upper triangular surfaces 16 and a third pair of upper triangular surfaces 16 by polishing the first pair of upper triangular surfaces 16 until the twelfth pair of upper triangular surfaces 16 are polished;

4.8 the waist is ground into a round shape.

The first included angle α is selected from 41.5-42.5 degrees, the second included angle β is selected from 35-39 degrees, the third included angle gamma is selected from 32-38 degrees, the fourth included angle omega is selected from 28-33 degrees, the fifth included angle phi is selected from 40-44 degrees, the first preset length h1 accounts for 20-50% of the distance from the apex to the waist, and the second preset length h2 accounts for 50-70% of the distance from the waist to the table board 1.

The invention has the beneficial effects that: this diamond facet is novel, and mesa 1 is regular dodecagon, perfect symmetry, and the structure of each facet sets up rationally, and the size is suitable, watches very pleasing to the eye under special magnifying glass, can observe the beautiful view that inside twelve butterflies waved around a flower elegantly moreover, and the purchase of promotion consumer that can be very big is expected.

Blanks of diamonds are multiplied by the cut sanding price and can be commercially successful by virtue of the unique facet design of the diamond itself.

As shown in figures 13 and 14, according to the light refraction principle, a new grinding process is adopted, light entering the diamond is refracted and reflected for multiple times, twelve butterflies are reflected inside the diamond, and the shape of dancing around a flower in the middle provides a new variety for diamond series and provides more consumption choices for consumers. Because the number of cutting surfaces is increased, the sparkle effect of the diamond can be improved by 5-10%.

Drawings

FIG. 1 shows a prior art diamond

FIG. 2 is a perspective view of a diamond

FIG. 3 is a schematic view of the first sole surface 3 processing

FIG. 4 is a schematic view of the process of manufacturing the second bottom rake face 31

FIG. 5 is a view of the second bottom rake face 31 after finishing processing

FIG. 6 is a schematic view of the process for manufacturing the table-board 1

FIG. 7 is a schematic view of the process of manufacturing the triangular kite surface 13

FIG. 8 is a view of the triangular kite surface 13 after being processed

FIG. 9 is a schematic view of the processing of the first upper triangular surface 14

FIG. 10 is a schematic view of the processing of the second upper triangular surface 15

FIG. 11 is a view of twelve pairs of upper triangular faces

FIG. 12 is a front view of a diamond

FIG. 13 is a view of the bottom view of the diamond showing the refraction effect

FIG. 14 is a top view of a diamond with refraction effect

In the figure, 1-table top, 12-main crown face, 13-triangular kite face, 14 first upper waist triangular face, 15-second upper waist triangular face, 16-pair of upper waist triangular faces, 101-main crown face intersection edge, 102-main crown face and table top intersection edge midpoint, 103-intersection point of edge 101 and girdle circle, 104-pair of upper waist triangular face and girdle circle intersection edge midpoint, 3-first sole face, 31-second sole rake tip face, 301-first sole rake tip point, 302-first sole face intersection edge, 303-second sole rake tip face intersection point, a is drill waist diameter, b is table top diameter, c is crown height, d is pavilion height, ∠ a is pavilion angle, ∠ b is crown and girdle included angle, ∠ c is pavilion and girdle included angle.

Detailed Description

The present invention is further illustrated by the following specific examples.

The invention also provides a method for processing the diamond with the twelve butterfly patterns in the interior, which comprises the following steps:

2, cutting the waist, and polishing the waist on the drill blank;

the step 3 comprises the following steps:

3.1 as shown in fig. 3, taking the plane of the waist as a reference plane, the reference plane is parallel to the plane of the table board 1, and twenty-four first underfoot surfaces 3 are ground towards the middle and lower part of the waist at a first included angle α, wherein the twenty-four first underfoot surfaces 3 intersect at a cone tip point 301, the twenty-four first underfoot surfaces 3 and the waist present a twenty-four pyramid, but the waist is finally ground into a circle;

3.2 based on the edge 302 intersected by two adjacent first foot faces 3, polishing a first second foot face 31 by a second included angle β towards two sides of the edge 302 respectively by using a conical tip point 301 as a starting point, or polishing the first second foot face 31 by a first preset length h1, wherein the two first foot faces 3 are used for polishing one second foot face 31, and polishing twelve second foot faces 31, wherein the polishing is performed by using two first foot faces 3, wherein each second foot face 31 is a quadrangle, as shown in fig. 5, it can be seen that the first second foot face 31 in fig. 4 is not a quadrangle, because the second foot face 31 in the figure is a plane, the plane quadrangle is modified, so that the first second foot face 31 in the figure is not a quadrangle, and the quadrangle can be polished in the actual working process, so that part of the adjacent second foot faces 31 are polished, but the second foot faces 31 are polished by using the second foot faces 31, and each second foot face 31 is a rhombus.

Since the length of the second bottom rake face 31 to be ground is h1, and the second bottom rake face 31 is quadrilateral, when the first second bottom rake face 31 is ground, the conical tip 301 formed by the intersection of twenty-four first bottom foot faces 3 is already ground, but for the convenience of understanding, it is assumed that the conical tip 301 exists until the completion of the twelfth second bottom rake face 31, and the angle of the second included angle β is smaller than that of the first included angle α.

The step 4 comprises the following steps:

4.1, grinding the crown part at a third included angle gamma to a rhombic second base rake tip surface 31 of the pavilion part to obtain a regular dodecagonal table surface 1 and twelve main crown surfaces 12 as shown in the figures 6 and 7;

4.2 on the basis of 4.1, as shown in fig. 7, based on the edge 101 where two adjacent main crown surfaces 12 intersect, grinding a first triangular kite surface 13 by using a fourth included angle Ω or according to a second preset length h2 and using the table top 1 as a starting point, wherein the table top 1 intersects with the first triangular kite surface 13, and two end points 102 of an intersection line are located at the central position of a line where the main crown surfaces 12 intersect with the table top 1;

4.3, grinding a second triangular kite surface 13 and a third triangular kite surface 13 by a method of grinding the first triangular kite surface 13, and repeating the steps until the twelfth triangular kite surface 13 is ground, and finishing the grinding as shown in the figure 8;

4.4 based on the rest of the ridge 101 intersected by the two main crown surfaces 12, polishing a first upper lumbar triangular surface 14 towards the center of the main crown surfaces 12 by taking the intersection point 103 of the ridge 101 intersected by the two main crown surfaces 12 on the lumbar circular plane as a starting point and a fifth included angle phi as shown in FIG. 9.

4.5 grinding a second upper lumbar triangle surface 15 towards the center direction of the other main crown surface 12 by a fifth included angle phi on the basis of the ridge 101 of the main crown surface 12 which is not ground in two adjacent main crown surfaces 12 in 4.4 and the intersection point 104 of the ridge 101 on the lumbar circle plane as a starting point on the basis of 4.4 as shown in fig. 10, wherein the second upper lumbar triangle surface 15 is symmetrical to the first upper lumbar triangle surface 14 by the ridge 101, and the first upper lumbar triangle surface 14 and the second upper lumbar triangle surface 15 are called as a first pair of upper lumbar triangle surfaces 16;

4.6 polishing a second pair of upper triangular surfaces 16 and a third pair of upper triangular surfaces 16 by a method for polishing the first pair of upper triangular surfaces 16 as shown in fig. 11 until the twelfth pair of upper triangular surfaces 16 are polished;

4.7 the waist is ground to be round.

In the processing step, the first included angle α is selected from 41.5-42.5 degrees, the second included angle β is selected from 35-39 degrees, the third included angle gamma is selected from 32-38 degrees, the fourth included angle omega is selected from 28-33 degrees, the fifth included angle phi is selected from 40-44 degrees, the first preset length h1 accounts for 20-50% of the distance from the apex 33 to the waist 2, and the second preset length h2 accounts for 50-70% of the distance from the waist 2 to the table 11.

The processing method is not the only processing method capable of processing the diamond, for example, the crown part can be processed and polished firstly, then the pavilion part can be processed and polished secondly, the first upper waist triangular surface 14 or the second upper waist triangular surface 15 can be processed and polished secondly, the triangular kite surface 13 can be polished firstly, the processing sequence of the diamond can still be polished to the diamond by changing the processing sequence, and the processing sequence is changed and combined in various ways due to multiple diamond processing steps, so that the description is not repeated, in the figure 1, b is 53-57% of a, c is 16.2% of a, d is 43.1% of a, waist height is 2-3% of a, ∠ a is 98 degrees, ∠ b is 34 degrees, and ∠ c is 40 degrees.

The present invention is not limited to the above preferred embodiments, and any modifications, equivalent substitutions and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A twelve-butterfly diamond comprising: a mesa (1), twelve triangle kite face (13), twelve main crown face (12), twelve first upper waist triangle face (14), twelve second upper waist triangle face (15), twenty-four first end foot face (3), twelve second end take off pointy face (31), its characterized in that: the second bottom rake pointed surface (31) is rhombic; the length h1 of the second bottom rake tip surface (31) accounts for 20-50% of the distance from the bottom rake tip (301) to the waist.

2. A one-flower twelve-butterfly diamond comprises a table board (1), twelve triangular kite faces (13), twelve main crown faces (12), twelve first upper waist triangular faces (14), twelve second upper waist triangular faces (15), twenty-four first bottom foot faces (3) and twelve second bottom pick-up tip faces (31), and is characterized in that the second bottom pick-up tip faces (31) are rhombic, a waist reference plane is used as a reference, a first included angle α between the first bottom foot faces (3) and the waist reference plane ranges from 41.5 degrees to 42.5 degrees, and a second included angle β between the second bottom pick-up tip faces (31) and the waist reference plane ranges from 35 degrees to 39 degrees.

3. A one-flower twelve-butterfly diamond comprises a table board (1), twelve triangular kite surfaces (13), twelve main crown surfaces (12), twelve first upper waist triangular surfaces (14), twelve second upper waist triangular surfaces (15), twenty-four first bottom foot surfaces (3) and twelve second bottom pick-off tip surfaces (31), and is characterized in that the length h1 of each second bottom pick-off tip surface (31) accounts for 20% -50% of the distance from a bottom tip (301) to a waist, the first bottom foot surfaces (3) and the waist reference surface are first included angles α in a range of 41.5-42.5 degrees, and the second bottom pick-off tip surfaces (31) and the waist reference surface are second included angles β in a range of 35-39 degrees.

4. A fancy twelve butterfly diamond as claimed in claim 1 or claim 2 or claim 3 wherein: the main crown surface (12) and the waist reference surface form a third included angle gamma, and the value range of gamma is 32-38 degrees; the triangular kite surface (13) and the waist reference surface form a fourth included angle omega, the value range of omega is 28-33 degrees, or the height h2 of the upper waist triangular surface accounts for 50% -70% of the distance from the waist to the table board (1); the first upper waist triangular surface (14) and the second upper waist triangular surface (15) form a fifth included angle phi with the waist reference surface, and the value range of phi is 40-44 degrees.

5. A processing method of twelve butterfly diamonds with one flower is characterized in that: the method comprises the following steps:

1, cutting a table top (1), and cutting a large plane on a drilling blank to be used as the table top (1);

2, cutting the waist, and polishing the waist on the drill blank;

the step 3 comprises the following steps:

3.1 taking the plane of the waist as a reference plane, wherein the reference plane is parallel to the plane of the table board (1), twenty-four first foot surfaces (3) are ground towards the middle lower part of the waist at a first included angle α, and the twenty-four first foot surfaces (3) are intersected at a rake point (301);

3.2 based on the intersected edge (302) of two adjacent first sole surfaces (3), polishing a first quadrilateral second sole rake surface (31) by using a second included angle β to the two sides of the edge (302) or according to a first preset length h1 by using a rake point (301) as a starting point, and then polishing twenty-four first sole surfaces (3) into twelve second sole rake surfaces (31) according to the same method, wherein the angle of the second included angle β is smaller than that of the first included angle α;

the step 4 comprises the following steps:

4.1, grinding the crown part into a regular dodecagonal table top (1) and twelve main crown surfaces (12) by aligning a second bottom rake sharp surface (31) of the pavilion part at a third included angle gamma;

4.2 on the basis of 4.1, grinding a first triangular kite surface (13) by using a fourth included angle omega or according to a second preset length h2 with the table top (1) as a starting point on the basis of an intersected edge of two adjacent main crown surfaces (12); two end points (102) of the triangular kite surface (13) on the table top (1) are positioned at the midpoint of the intersection line of the main crown surface (12) and the table top (1);

4.3 grinding twelve triangular kite surfaces (13) by a method of grinding a first triangular kite surface (13);

4.4 based on the rest section of the arris (101) of the main crown surface (12), grinding a first upper waist triangular surface (14) towards the center direction of the main crown surface (12) by taking the intersection point (103) of the arris (101) which is intersected by the two main crown surfaces (12) on the waist circle as a starting point and a fifth included angle phi;

4.5 grinding a second upper lumbar triangular surface (15) symmetrical to the first upper lumbar triangular surface (14) towards the center direction of the other main crown surface (12) by taking an edge (101) of the main crown surface (12) which is not ground in two adjacent main crown surfaces (12) in 4.4 as a symmetry axis and an intersection point (103) of the edge (101) on a lumbar circle as a starting point on the basis of 4.4;

4.6 two symmetrical first upper waist triangular surfaces (14) and second upper waist triangular surfaces (15) are called a pair of upper waist triangular surfaces (16);

4.7 polishing a second pair of upper triangular surfaces (16) and a third pair of upper triangular surfaces (16) by a method of polishing the first pair of upper triangular surfaces (16) until the twelfth pair of upper triangular surfaces (16) are polished;

4.8 the waist is ground into a round shape.

6. The method of claim 5, wherein said first angle α is selected between 41.5-42.5 degrees, said second angle β is selected between 35-39 degrees, said third angle γ is selected between 32-38 degrees, said fourth angle Ω is selected between 28-33 degrees, said fifth angle Φ is selected between 40-44 degrees, said first predetermined length h1 is between 20% -50% of the apex-to-waist distance, and said second predetermined length h2 is between 50% -70% of the waist-to-table (1) distance.