1, standard round bright cutting.
Shape: round
Cutting: bright/brilliant
Origin: 19 19.
Diamond cutters in the market are generally standard round diamonds. This cut has 58 faces. The top surface is called the table top, and the part with the largest diameter is the waistline, above which is the crown, and below which is the pavilion.
19 19, Marcel Tolkowsky drew a cutting and grinding pattern of a round drill through optical calculation, which can well reflect the fire luster. This cutting mill includes 58 facets, such as table top, upper and lower waist surfaces, star-shaped facets and sharp bottom. For those who score below 25 points, but are four-corner rough stones, cutting according to this ratio will lose the most weight. So this can only be used for reference. Tokowski's cutting ratio is: average waist diameter: 100% table top: 53.0% crown height: 16.2% pavilion height: 43. 1% crown angle: 34 degrees 30 minutes, pavilion angle: 40 degrees 45 minutes. This cutting ratio lays the foundation for ideal diamond cutting. Different regions have different cutting ratios. Tokowski cutting is also called American cutting, and others are German cutting and European cutting.
2. Oval Brilliant Cut
Shape: oval
Cutting: bright/brilliant
Origin:19th century
There is a bow tie effect. Its original stone retention rate can reach 50% to 60%, which is suitable for octahedral diamond original stone. Because it can retain the high quality of diamonds, it is often used in many ancient diamonds that have been cut again.
Profile requirements: symmetrical shoulders.
3. Pear-shaped bright cutting
Shape: pear-shaped
Cutting: bright/brilliant
Origin: In the17th century, it was also called tearing cutting with bow tie effect or Pendloque cutting.
Pear-shaped cutting was very popular in Louis XIV of France. Nearly 20% of the famous diamonds in history have adopted this kind of cutting, including Cullinan 1, the largest diamond in the world. This tool is suitable for machining rough diamonds with damaged or defective corners at one end. Pay attention to protect sharp corners when inlaying. Outline requirements: the two flanks are symmetrical and the sharp corners are free from defects.
4. Marquise's bright cut
Shape: olive tip.
Cutting: bright/brilliant
Origin:17th century, during Louis XIV of France.
It is also translated as horse eye cutting machine or ship cutting machine. This cut diamond has sharp corners at both ends and looks like a stone, hence its name. There is a bow tie effect.
This kind of cut rough stone has a low retention rate and is characterized by sharp corners at both ends, where inclusions can be well covered and the sparkle at the sharp corners is extremely high. Pay attention to protect sharp corners when inlaying.
Outline requirements: symmetrical sharp corners, no defects.
5. Square bright cutting
Shape: square
Cutting: bright/bright or mixed.
Origin: It was invented by Belgian craftsmen in the middle of last century. This cutting has been continuously improved, and a series of improved forms have been derived.
Because its improved form has the characteristics of step cutting, it can also be classified as mixed cutting.
Square cutters have a square or rectangular shape, usually with 76 facets. But there are also 6 1, 10 1 facet or 144 facet. Among them, 10 1 faceted square bright cutting is the registered patent cutting of E.F.D diamond company, that is, princess side.
Square cutting can be diversified, but generally the crown is shallow, the table is large and the pavilion is deep.
This cutting method has higher original stone retention rate than other bright cutting methods, but it is not suitable for shallow pavilion drilling blanks.
The brightness and flicker produced by sharp corners and pavilion facets reduce the visibility of inclusions and slightly "improve" the color level of diamonds. Compared with round cut diamonds, square cut diamonds with the same weight seem to be 65,438+05% larger in appearance.
Square is suitable for seamless setting of closely arranged diamonds, but diamonds of other shapes can't, but the sharp corners need to be protected when setting.
6. Heart-shaped bright cut
Shape: heart-shaped
Cutting: bright/brilliant
Origin: modern times
The shape of a diamond consists of two symmetrical wings with a groove in the middle and a sharp corner at the bottom, which looks like a heart.
Heart-shaped cut diamonds are shallow and suitable for rough diamonds with irregular shapes and flat overall. It can remove the inclusions in the original groove and improve the purity of the diamond, but the retention rate of this cut rough stone is low.
The shape evaluation of heart-shaped diamonds mainly focuses on the symmetry of the two flanks and the fullness of the shape.
7. Emerald is thinking about tricks
Shape: rectangle
Cutting: step type
Origin: ancient times
A typical derivative processing method of step cutting is that all sections are parallel or perpendicular to the square outer waistline of the diamond, and the shape is rectangular, the pavilion and crown are flat, and the bottom tip is straight. Because it is often used in the processing of emeralds, it is named.
Emerald-cut diamonds are difficult to hide inclusions, and are suitable for rough stones with high clarity, rectangles, corners or slightly damaged inclusions, and the retention rate of rough stones can reach 60% to 70%.
Outline requirements: pay attention to the size of the four corners cut off, and the line and surface must be strictly parallel.
8. Shape: rectangular radiation cutting
Cutting: mixed type
Origin: 1977
Radiation cutting was invented in 1977. Craftsmen hope to combine the elegant appearance of emerald cutting with the brightness of circular cutting to create this kind of cutting.
The radiation has a rectangular shape and four corners are cut off. It not only takes into account the retention rate of emerald-cut plateau stone and the easy-to-match shape, but also has excellent optical properties such as round and brilliant cutting.
Radiation cutting is suitable for rough stones with slightly rectangular shape, damaged corners and defects, and the retention rate of rough stones is high.