GEMSTONE

Abstract

The invention relates to a gemstone including a crown having a multiplicity of crown facets and a table, a girdle, and a pavilion having a multiplicity of pavilion facets, wherein a crown angle is between 34.5° and 35.5°, and is preferably 35°, and a pavilion angle is between 40° and 41°, preferably between 40.2° and 40.8°, and is particularly preferably 40.5°.

Description

The invention relates to a gemstone, in particular a diamond, but also other gemstones, e.g. precious stones or semi-precious stones, or also synthetic gemstones.

The prior art discloses gemstones with different cuts. In particular, gemstones having a brilliant cut or octagonal cut have become popular. However, in some circumstances, these cuts can be disadvantageous. A main problem found in gemstones, in particular diamonds, if they are incorporated for example in a dial of a wristwatch is the size and the interplay between the individual facets of the stones. A dial fully set with small brilliants can accommodate up to eight hundred individual brilliants which, having an individual diameter of 1 mm or even less, are very small. If, in such a case, brilliants which have the full number of facets made up of the customary fifty-six facets plus the table facet, then the reflected light divides up into so many small, individual flashes of light that they can no longer be discerned as sparkle by the viewer since they lie below the visual threshold. In the case of the full number of facets of a conventionally brilliant-cut diamond, an incident light beam, at most angles of incidence, is split up into a few hundred small light beams. If this takes place in the case of a stone which has a diameter of just 1 mm, and in which the individual facets are only around 0.1 mm, then the human eye is no longer angle to discern the individual flashes of light as such and sees only diffuse lighting. It is only in the case of an extremely pronounced, punctiform light source that sparkle and dispersion are still discernible.

It is therefore the case that a small brilliant-cut gemstone does not have optimum dispersion behavior and sparkle.

Human powers of perception usually function up to a size of 0.2 mm. This means that two points which are spaced apart from one another by a distance of 0.2 mm are still discerned by the viewer as two separate points. If the distance decreases to 0.1 mm, the viewer discerns the two points merely as a single point. In the case of the octagonal cut, which is distinguished in that it has only sixteen facets (eight facets in the crown and eight facets in the pavilion) and a table facet, the individual facets of the crown of the gemstone are usually still above the size at which items can be perceived individually. This means that the naked eye of a viewer can make out a structure of the facet arrangement in the gemstone. It is only with very great difficulty that a stone setter can arrange the individual gemstones in a certain way so that the individual stones have the eight facets aligned at certain intervals. Even if the stone setter were to make the effort to do this, and he would succeed in achieving such regular intervals in the setting of eight hundred brilliants, such a regular-interval arrangement would, in most cases, be problematic. The reason for this is that said regular-interval arrangement would itself conflict in visual terms with other design elements of the timepiece, for example with a circular shape of the dial. If the individual octagonal-cut stones, however, do not have their facets aligned, this gives the impression of disharmony in the dial.

The octagonal cut also has the disadvantage that breaking up the circular structure into just eight segments is accompanied by a certain loss of light. At each “corner” of the stone, at which the individual facets are located opposite one another at a certain angle, the stone loses light to some extent. In this respect, an octagonal-cut gemstone does not give an optimum light yield.

It is the object of the invention to propose a gemstone which has improved optical properties, even if the gemstone is small.

This object is achieved by the combination of features in the independent claim.

In particular, the object is achieved by a gemstone which comprises a crown having a multiplicity of crown facets and a table, a girdle, and a pavilion having a multiplicity of pavilion facets. A crown angle is advantageously between 34.5° and 35.5°, and is preferably 35°, wherein a pavilion angle is between 40° and 41°, preferably between 40.2° and 40.8°, and is particularly preferably 40.5°. In other words, the angle of the outer crown facets in relation to the gemstone-girdle plane, which runs perpendicularly to a vertical axis of the gemstone or a longitudinal axis of the gemstone, is between 34.5° and 35.5°, and is preferably 35°. The angle of the pavilion facets in relation to a horizontal axis of the gemstone is between 40° and 41°, preferably between 40.2° and 40.8°, and is particularly preferably 40.5°. In particular, the crown angle is 35° and the pavilion angle is 40.5°.

With the crown angle and the pavilion angle defined in this way, the light is conducted within the stone such that the total reflection angle can be utilized correctly and does not work against the light yield of the gemstone. Total reflection takes place when a light beam attempting to exit from an optically denser medium into an optically thinner medium does so at an angle below the total reflection angle. If the light beam is incident on the boundary of the two optical media within the total reflection angle, it is reflected “in total”. This means that zero percent of the light is lost during the operation. It should also be noted that the peripheral regions of the gemstones are the sensitive regions in which usually greater losses of light occur than in the case of light which is incident on the inner part of the table facet. The angle arrangement proposed avoids a loss in the light which is incident on the periphery of the gemstone from above. This results in an optimum overall yield of the incident light for the gemstone.

The gemstone described, in particular on account of its crown angle, also has the advantage of a high level of dispersion. Dispersion is to be understood to mean the separation of the white light into its spectral colors. In other words, the term dispersion refers to the different amounts of refraction in accordance with the different refractive indices of the different wavelengths of the light. As a result of the high level of dispersion of the gemstone, the gemstone becomes vibrant and a natural coloring of the gemstone takes on secondary importance. This is highly advantageous in particular in the case of gemstones having a “low-level” coloring, because a viewer is therefore not capable of discerning the low-level coloring and thus deems the gemstone to be of great interest. The reason is that the impression of white light separated into the spectral colors, that is to say the simultaneous occurrence of the various spectral colors (colors of the rainbow), makes it impossible for the viewer to make out the original color. In other words, the spectral colors dominate the visual impression and override the color perception in respect of the gemstone.

It is also the case with other characteristics of a gemstone, for example when a gemstone, rather than being flawless, has inclusions which could possibly be made out by the naked eye, that these inclusions are not evident in the case of pronounced dispersion and a high overall light yield.

The gemstone proposed has the further advantage that the gemstone presents an esthetically interesting and clearly recognizable light pattern under a kaleidoscope. In particular on account of the crown angle defined according to the invention, and of the overall light yields which is optimized as a result, the situation where the light pattern loses its optical effect and does not appear striking is avoided. The result is therefore a clear light pattern which, in the case of most facet arrangements of the gemstones, creates a star shape made up of arrows when the gemstone is viewed from above. When the gemstone is viewed from the rear, the light pattern creates possibly a flower or an arrangement of heart shapes.

The principle of a kaleidoscope, in some cases also referred to as a “Hearts & Arrows” scope, is that in this case the light which is incident on the gemstone from above, in a direction perpendicular to the horizontal axis of the gemstone, is a white, unfiltered light. However, the “scattered light”, which is incident on the gemstone at an angle of greater than 20° in relation to the vertical axis of the gemstone, is color-filtered by the colored inner wall of the scope and creates a striking color (red or blue) in the stone, its luminosity also being reduced as a result of the color filtering. Consequently, the white light, which is incident directly from above, is dominant and is optically clearly distinguished from the more laterally incident light. This separation of strong white light, which is incident vertically on the stone, and a reduced level of colored, laterally incident light results in the visual impression given by the white light being up to ten times stronger than that given by the somewhat more obliquely conducted colored light.

The girdle here corresponds to an encircling edge or a separating periphery between the crown and the pavilion in cut gemstones. The crown is the upper part of the gemstone, which is located above the girdle. Accordingly, the pavilion is the lower part of the diamond, which is located beneath the girdle. The table (table facet) is the largest facet of the crown of the gemstone. The crown angle is that angle which, when the gemstone is viewed from this side, is formed between the lateral boundary line of the crown and the girdle plane, said boundary line being formed by an orthogonal projection of a crown facet onto a plane which contains the longitudinal axis of the gemstone. The girdle plane is that plane which is arranged parallel to the table and in which the gemstone has the largest cross-sectional extent. The girdle plane is oriented perpendicularly to the longitudinal direction of the gemstone. The pavilion angle is that angle which, when the gemstone is viewed from the side, is formed between the lateral boundary line of the pavilion and the girdle plane, said boundary line being formed by an orthogonal projection of a pavilion facet onto a plane which contains the longitudinal axis of the gemstone.

The dependent claims contain advantageous developments and aspects of the invention.

The crown of the gemstone advantageously has one or two angle planes. “Angle plane” is to be understood to mean a row of facets which, as seen in the direction from the girdle of the gemstone, that is to say of the outer boundary circle, to the center of the stone, that is to say to the center of the table, have a quite specific angle in relation to the horizontal plane. The sparkle of the gemstone increases as a result of one or two angle planes being provided instead of three angle planes, as is the case for a brilliant-cut gemstone. This advantage is particularly important in the case of small gemstones, since it is predominantly here where the problem arises of the sparkle of the individual facets decreasing on account of their small size. Furthermore, the provision of one or two angle planes gives rise to an esthetically interesting and high-quality light pattern under a kaleidoscope. Moreover, the vibrancy of the gemstone is optimized in the critical regions of a shallow viewing angle. As a result, it is not just the case that the gemstone is vibrant and sparkles to a pronounced extent in plan view; in addition, the flashes of red and blue light produced by dispersion of the light in the gemstone are also clearly visible from a shallow viewing angle. This advantage is obvious, in particular, not just in the individual gemstone, but is of quite particular interest when an entire surface is to be set with a large number of smaller gemstones. This is the case, for example, for a pave-set surface of a piece of jewelry or a dial of a timepiece. As a result of the reduced number of angle planes, such, usually diamond-set, regions of a piece of jewelry or of a wristwatch have a particularly attractive appearance when viewed laterally from a shallow angle, since the viewer's eye can clearly make out the flashes of light. Both the “sparkle” with white light and the flashes of light caused by the dispersion can be clearly made out in the case of such a gemstone-set surface.

The table is preferably a regular dodecagon. This means that the gemstone is cut with facets at 12 regular intervals. The 12-increment graduation increases the overall light yield of the gemstone. In particular, a combination of a 12-increment graduation and of one or two angle planes in the crown of the gemstone achieves a higher level of sparkle while, at the same time, maintaining the overall light yield.

Furthermore, the sum of the crown facets and of the pavilion facets is preferably forty-eight, thirty-six or twenty-four facets. Therefore, the crown facets are reduced in number in comparison with a brilliant-cut gemstone. This helps to increase the sparkle of the gemstone.

Furthermore, the reduced number of crown facets, and consequently the reduced number of facets for the gemstone overall, results in an optically impressive or striking light pattern under a kaleidoscope. In addition, the specific number of facets of the crown provides for the vibrancy of the gemstone to be optimized in the critical regions of a shallow viewing angle.

It is preferable for the pavilion facets to comprise lower girdle facets and for the crown facets to comprise upper girdle facets, wherein each of the lower girdle facets is aligned with precisely one of the upper girdle facets. Positioning the lower girdle facets and the upper girdle facets opposite one another avoids the situation where a flash of light is divided into two parts as a result of being incident on a double facet in the stone. The sparkle of the gemstone is therefore increased. Moreover, the alignment of the upper girdle facets in relation to the lower girdle facets achieves a clear light pattern of the gemstone under a kaleidoscope.

A further aspect of the invention relates to a timepiece having at least one gemstone which is arranged, in particular, in a dial/hands compartment. The dial/hands compartment is the compartment, or the accommodating chamber, of the timepiece in which a dial and/or at least one hand of the timepiece are arranged. The gemstone is particularly preferably arranged in the dial. The dial contains preferably more than two hundred gemstones, particularly preferably more than four hundred to eight hundred gemstones. In particular, are the gemstones each have a diameter of smaller than 2 mm, particularly preferably equal to, or smaller than, 1 mm.

The in respect of the abovedescribed gemstone are also given here. In particular, the abovedescribed gemstone optimizes the optical properties which are important for a gemstone in the dial/hands compartment of the timepiece, that is to say beneath a watchglass of the timepiece.

A 12-increment graduation of the facets in the case of a preferred configuration of the gemstone does away with the impression of disharmony in the dial.

A reduction in the overall number of facets in the individual stones, and the fact that the angle planes of the crown facets are reduced to one or two angle planes, cause a diamond-set dial to give a harmonious and homogeneous impression, on the one hand. On the other hand, clear flashes both of the white light and of the split-up spectral colors of the light can be made out in any position, even at relatively shallow viewing angles.

Therefore, the abovedescribed gemstone constitutes a considerable improvement in the effect of the gemstone, in particular of a diamond, within the dial/hands compartment. This applies all the more so since the watchglass, which is positioned over the dial or an inner bezel, does reduce the effect of the light to a certain extent. It is the case that both the light which is incident on the diamonds is reduced by the watchglass and the light which exits from the diamonds again is largely absorbed by the watchglass at shallow exit angles and is reduced by approximately 10% to 30% at steep exit angles.

The optimization of dispersion and sparkle and the improvement in the fire of the gemstone, in particular at shallow viewing angles, “compensates” for the reduction in the light caused by the watchglass, and therefore the gemstone creates a good effect beneath the watchglass. This is particularly important in the case of gemstones being used in timepieces or wristwatches.

Further details, advantages and features of the present invention can be gathered from the following description of exemplary embodiments with reference to the drawing, in which identical, or functionally identical, parts are each denoted by the identical reference sign. In the drawing:

FIG. 1(a)-(d) show different views of a gemstone according to a first exemplary embodiment of the present invention,

FIG. 2(a)-(d) show different views of a gemstone according to a second exemplary embodiment of the present invention,

FIG. 3(a)-(e) show different views of the gemstone according to a third exemplary embodiment of the present invention,

FIG. 4(a)-(d) show different views of a gemstone according to a fourth exemplary embodiment of the present invention,

FIG. 5(a)-(d) show different views of a gemstone according to a fifth exemplary embodiment of the present invention, and

FIG. 6(a)-(d) show different views of a gemstone according to a sixth exemplary embodiment of the present invention.

A gemstone 1 according to a first exemplary embodiment of the present invention will be described in detail hereinbelow with reference to FIG. 1.

In particular, FIG. 1(a) shows a plan view, FIG. 1(b) shows a side view, and FIG. 1(c) shows a bottom view, of the gemstone 1. FIG. 1(d) shows a light pattern of the gemstone 1 seen from above under a kaleidoscope.

As can be seen from FIG. 1(b), the gemstone 1 has a crown 2, a girdle 3 and a pavilion 4.

A crown angle α of the gemstone 1 is between 34.5° and 35.5°, and is preferably 35°. Furthermore, a pavilion angle β of the gemstone 1 is between 40° and 41°, preferably between 40.2° and 40.8°, and is particularly preferably 40.5°. In particular, the crown angle α is 35° and the pavilion angle β is 40.5°.

The crown 2 comprises a table 10 and a multiplicity of crown facets 11, 12, wherein the pavilion 4 has a multiplicity of pavilion facets 13, 14. In particular, the crown facets 11, 12 comprise first crown facets 11 and second crown facets (upper girdle facets) 12. Furthermore, the pavilion facets 13, 14 comprise first pavilion facets (lower girdle facets) 13 and second pavilion facets 14.

The table 10 is preferably designed in the form of a regular dodecagon.

The first crown facets 11 each have a broad side adjoining the table 10, wherein the second crown facets 12 extend from the table 10 to the girdle 3 and have a broad side adjoining the girdle 3. This creates the shape of an internal star, as seen in the plan view of FIG. 1(a).

The first crown facets 11 are in the shape of a pentagon and the second crown facets 12 are in the shape of a triangle. The first pavilion facets 13 are in the shape of a triangle and the second pavilion facets 12 are in the shape of a pentagon.

In particular, this embodiment of the gemstone 1 has twelve such first crown facets 11 and twelve such second crown facets 12. Therefore, the gemstone 1 has a total of twenty-four crown facets.

The first pavilion facets 13 each have a broad side adjoining the table 10, wherein the second pavilion facets 14 extend from the table 10 to the girdle 3. In particular, this embodiment of the gemstone 1 has twelve such first pavilion facets 13 and twelve such second pavilion facets 14. Therefore, the gemstone 1 has a total of twenty-four pavilion facets.

The overall number of facets of the gemstone 1 is 49 facets (48 crown and pavilion facets plus the table 10).

The crown 2 of the gemstone 1 has two angle planes, wherein the one angle plane comprises the first crown facets 12 and the other angle plane comprises the second crown facets 13.

Correspondingly, the pavilion 3 has two angle planes, wherein the one angle plane comprises the first pavilion facets 13 and the other angle plane comprises the second pavilion facets 14.

The pavilion 2 tapers to a culet 5. The culet 5 is formed by the second pavilion facets 14.

Each of the second crown facets 12 is advantageously aligned with precisely one first pavilion facet 13.

FIG. 2 illustrates a gemstone 1 according to a second exemplary embodiment of the present invention.

In particular, FIG. 2(a) shows a plan view, FIG. 2(b) shows a side view, and FIG. 2(c) shows a bottom view, of the gemstone 1.

The second exemplary embodiment differs from the first exemplary embodiment basically in that the first crown facets 11 each have a broad side adjoining the table 10 and extend from the table 10 to the girdle 3. The second crown facets 12 each have a broad side adjoining the girdle 3.

Furthermore, the first crown facets 11 are each in the shape of a triangle and the second crown facets 12 are in the shape of a pentagon.

This creates the shape of an external star, as seen in the plan view of FIG. 2(a).

FIG. 2(d) shows a light pattern of the gemstone 1 as seen from above, when the gemstone 1 is viewed under a kaleidoscope.

FIG. 3 illustrates a gemstone 1 according to a third exemplary embodiment of the present invention.

In particular, FIG. 3(a) shows a plan view, FIG. 3(b) shows a side view, and FIG. 3(c) shows a bottom view, of the gemstone 1.

In this exemplary embodiment, the first crown facets 11 each have a broad side adjoining the table 10 and extend from the table 10 to the girdle 3, as in the second exemplary embodiment.

In the third exemplary embodiment, however, the second crown facets 12 each have a broad side adjoining the girdle 3 and extend from the table 10 to the girdle 3.

Therefore, both the first crown facets 11 and the second crown facets 12 extend from the table 10 to the girdle 3.

The first crown facets 11 and the second crown facets 12 are of triangular design.

This creates the shape of a full star, as seen in the plan view of FIG. 3(a).

In this exemplary embodiment, the crown facets 11, 12 form just a single angle plane in the crown 2 of the gemstone 1, since all the crown facets 11, 12 extend from the girdle 3 to the table 10. This means that all the crown facets 11, 12 are positioned at the same angle, which is equal to the crown angle.

FIGS. 3(d) and (e) show light patterns of the gemstone 1 as seen from above and beneath under a kaleidoscope.

FIG. 4 illustrates a gemstone 1 according to a fourth exemplary embodiment of the present invention.

In particular, FIG. 4(a) shows a plan view, FIG. 4(b) shows a side view, and FIG. 4(c) shows a bottom view, of the gemstone 1.

In this exemplary embodiment, the crown 2 just has a multiplicity of first crown facets 11. This means that the crown facets comprise only the first crown facets 11. The first crown facets 11 are each designed in the form of a quadrilateral and adjoin the table 10 and the girdle 2.

The gemstone 1 therefore has just a single angle plane in the crown 2.

The gemstone 1 has twelve crown facets, or twelve first crown facets 11, and twenty-four pavilion facets 13, 14.

The overall number of facets of the gemstone 1 is 37 facets (36 crown and pavilion facets plus the table 10).

Each of the first crown facets 11 is advantageously positioned opposite a first pavilion facet 13.

FIG. 4(d) shows a light pattern of the gemstone 1 as seen from above when the gemstone 1 is viewed under a kaleidoscope.

FIG. 5 shows a gemstone 1 according to a fifth exemplary embodiment of the present invention.

In particular, FIG. 5(a) shows a plan view, FIG. 5(b) shows a side view, and FIG. 5(c) shows a bottom view, of the gemstone 1.

The difference between the gemstone 1 according to the fifth exemplary embodiment and the gemstone 1 according to the fourth exemplary embodiment is that the first crown facets 11 in the fifth exemplary embodiment are offset in the circumferential direction, or in the direction of the girdle 3, in relation to the first pavilion facets 13.

As in the fourth exemplary embodiment, the gemstone 1 of FIG. 5 has a single angle plane in the crown 2.

FIG. 5(d) shows the resulting light pattern of the gemstone 1 as seen from above when the gemstone 1 is viewed under a kaleidoscope.

FIG. 6 illustrates a gemstone 1 according to a sixth exemplary embodiment of the present invention.

In the sixth exemplary embodiment, the crown 2 of the gemstone 1 corresponds in terms of construction to the crown 2 of the gemstone 1 according to the fourth exemplary embodiment.

In particular, FIG. 6(a) shows a plan view, FIG. 6(b) shows a side view, and FIG. 6(c) shows a bottom view, of the gemstone 1.

In the exemplary embodiment of FIG. 6, however, the pavilion 4 has just a single angle plane, which comprises a multiplicity of first pavilion facets 13. This means that the pavilion facets comprise only the first pavilion facets 13. In particular, the pavilion 4 has twelve pavilion facets, or twelve first pavilion facets.

The first pavilion facets 13 are each configured in the form of a triangle and extend from the culet 5 to the girdle 3. The first pavilion facets 13 here have a broad side adjoining the girdle 3.

It is also the case that the culet 5 is formed by the first pavilion facets 13.

The overall number of the facets of the gemstone 1 is 25 facets (24 crown and pavilion facets plus the table 10).

FIG. 6(d) shows the resulting light pattern of the gemstone 1 as seen from above when the gemstone 1 is viewed under a kaleidoscope.

The abovedescribed embodiments of the gemstone 1 have a large number of advantages at the same time.

In particular, the abovedescribed gemstones 1 reflect back into the viewer's eye a very high percentage of the light which is incident on them. It is also the case that the highest possible fraction of incident white light dispersed into the spectral colors can be reflected into the viewer's eye by the gemstones 1. Furthermore, a large fraction of the incident light is reflected as individual flashes of light in the case of the gemstones 1. This means that the gemstones 1 do not convert focused light into scattered, diffuse light. Furthermore, the gemstones 1 are designed such that they reflect the incident light to the viewer such that, when viewed from pretty much all positions (even at shallow angles), the gemstones are highly luminescent, exhibit dispersion and sparkle. Moreover, the gemstone 1 are optimized for use in a timepiece. This means that the gemstones 1, as far as their sparkle and dispersion behavior are concerned, have fewer, but for all that more pronounced, flashes of light, wherein the gemstones 1 sparkle, and emit dispersion clusters, even at flat viewing angles. Furthermore, the gemstones 1 according to the exemplary embodiments explained above give a harmonious impression which does not dominate the design. Finally, the gemstones 1 are kaleidoscope-compatible. This means that the gemstones 1 produce an esthetically pleasing and clearly evident light symbol when the gemstones 1 are viewed under a kaleidoscope.

In other words, the interplay of individual optimized optical features is optimized as far as the gemstones 1 described above are concerned.

Alongside the written description of the invention documented above, the disclosure of the invention is supplemented by reference hereby being made explicitly to the illustration thereof in FIGS. 1 to 6.

LIST OF REFERENCE SIGNS

• 1 Gemstone
• 2 Crown
• 3 Girdle
• 4 Pavilion
• 5 Culet
• 10 Table
• 11 First crown facets
• 12 Second crown facets
• 13 First pavilion facets
• 14 Second pavilion facets
• α Crown angle
• β Pavilion angle

Claims

1. A gemstone, comprising:

a crown having a multiplicity of crown facets and a table,

a girdle, and

a pavilion having a multiplicity of pavilion facets,

wherein:

a crown angle is between 34.5° and 35.5°, and a pavilion angle is between 40° and 41°.

2. The gemstone as claimed in claim 1, wherein the crown of the gemstone has one or two angle planes.

3. The gemstone as claimed in claim 1, wherein the table is a regular dodecagon.

4. The gemstone as claimed in claim 1, wherein the sum of the crown facets and of the pavilion facets is forty-eight or thirty-six or twenty-four facets.

5. The gemstone as claimed in claim 1, wherein the pavilion facets comprise lower girdle facets and the crown facets comprise upper girdle facets, wherein each of the lower girdle facets is aligned with precisely one of the upper girdle facets.

6. A timepiece having at least one gemstone, which is arranged in a dial/hands compartment or in a watchglass.

7. The gemstone as claimed in claim 1, wherein the crown angle is 35°.

8. The gemstone as claimed in claim 1, wherein the pavilion angle is between 40.2° and 40.8°.

9. The gemstone as claimed in claim 1, wherein the pavilion angle is 40. 5°.

10. The gemstone as claimed in claim 2, wherein the table is a regular dodecagon.

11. The gemstone as claimed in claim 2, wherein the sum of the crown facets and of the pavilion facets is forty-eight or thirty-six or twenty-four facets.

12. The gemstone as claimed in claim 3, wherein the sum of the crown facets and of the pavilion facets is forty-eight or thirty-six or twenty-four facets.

13. The gemstone as claimed in claim 2, wherein the pavilion facets comprise lower girdle facets and the crown facets comprise upper girdle facets, wherein each of the lower girdle facets is aligned with precisely one of the upper girdle facets.

14. The gemstone as claimed in claim 3, wherein the pavilion facets comprise lower girdle facets and the crown facets comprise upper girdle facets, wherein each of the lower girdle facets is aligned with precisely one of the upper girdle facets.

15. The gemstone as claimed in claim 4, wherein the pavilion facets comprise lower girdle facets and the crown facets comprise upper girdle facets, wherein each of the lower girdle facets is aligned with precisely one of the upper girdle facets.

16. The timepiece according to claim 6, wherein the at least one gemstone comprises:

a crown having a multiplicity of crown facets and a table;

a girdle; and

a pavilion having a multiplicity of pavilion facets,

wherein a crown angle is between 34.5° and 35.5°, and a pavilion angle is between 40° and 41°.