|
Colorless diamond can be confused with precious beryl, cerussite, sapphire, topaz, zircon, sphalerite, and scheelite. Apart from these, there are various synthetic stones that are used to imitate diamond. Especially, YAG, galliant, linobate, and zirconia.
As mentioned before, truly colorless stones are rear as most diamonds occur in different colors including yellow, brown, green, black, and blue. The most common impurity is nitrogen, which gives rise to brown, yellow, green and black diamond depending on the amount present and its distribution in the crystal structure. Blue diamonds which are probably the most famous of all colored diamonds contain minute traces of boron.
Cutting and polishing diamond is considered as an art as it is the only way to make the most of diamond’s superb qualities. Early diamond cutting was minimal in order to minimize the waste of cutting process but it did not bring out the brilliance of the stone. During the centuries, more and more facets were added to the diamond, focusing on bringing out the brilliance of the stone rather than simply minimizing the cutting waste. Today’s modern round brilliant cut was designed by Marcel Tolkowsky which has 57 to 58 precisely angled facets. His design uses mathematical principles to reflect the maximum amount of brilliant light entering the stone back to the eye of the viewer. In the nutshell, the following process can be distinguished in the working of diamond: pre-examination, cleaving or sawing, bruiting, cutting, and polishing.
Making artificial diamonds has been a unreachable dream for ages. Finally, in 1955, this dream came true when General Electric Company succeeded in synthesizing small diamond crystals from pure graphite under enormous temperatures and pressures.
As mentioned before, truly colorless stones are rear as most diamonds occur in different colors including yellow, brown, green, black, and blue. The most common impurity is nitrogen, which gives rise to brown, yellow, green and black diamond depending on the amount present and its distribution in the crystal structure. Blue diamonds which are probably the most famous of all colored diamonds contain minute traces of boron.
Cutting and polishing diamond is considered as an art as it is the only way to make the most of diamond’s superb qualities. Early diamond cutting was minimal in order to minimize the waste of cutting process but it did not bring out the brilliance of the stone. During the centuries, more and more facets were added to the diamond, focusing on bringing out the brilliance of the stone rather than simply minimizing the cutting waste. Today’s modern round brilliant cut was designed by Marcel Tolkowsky which has 57 to 58 precisely angled facets. His design uses mathematical principles to reflect the maximum amount of brilliant light entering the stone back to the eye of the viewer. In the nutshell, the following process can be distinguished in the working of diamond: pre-examination, cleaving or sawing, bruiting, cutting, and polishing.
Making artificial diamonds has been a unreachable dream for ages. Finally, in 1955, this dream came true when General Electric Company succeeded in synthesizing small diamond crystals from pure graphite under enormous temperatures and pressures.
how to evaluate diamonds
|
Cut of the stone is the most important parameter that is used to determine the value of a diamond. In addition to cut, carat weight, color, and clarity are also used to determine the value of a diamond (these four parameter are known as four Cs). A badly cut stone will lack the brilliance of a well-cut diamond. This can have a huge impact on the value of the diamond (round brilliant cut is by far the most popular cut). The next parameter in determining the value of diamond is carat weight (the size of the diamond measured in carats). The bigger the diamond is, the higher value it will have and the value rises steeply for larger stones. Diamond is a colorless stone, therefore, talking about the color of a diamond might seem strange. However, subtle gradation of color exhibited by
|
diamonds is very important in determining the value of a diamond. Clarity is the last of the four Cs that are used to determine the value of a diamond. The term clarity is referred to the inclusions and imperfections (cracks on the surface) that are found in the stone. Obviously, the more inclusions and imperfection a diamond has, less value it will have.
List of Famous Diamonds
Following is the list of famous diamonds because of their size, beauty, or their adventurous past:
1) Dresden, 41 carats, kept in Green Hall in Dresden 2) Hope, 45.52 carats, since 1958 is kept in the Smithsonian Institution, Washington, D.C. 3) Star of Africa, 530.20 carats, largest cut diamond, kept in Tower of London 4) Sancy, 55 carats, since 1906 belonging to the Astor family, Londin 5) Tiffany, 128.51 carats 6) koh-i-noor, 108.92 carats, bought 1739 by the Shah of Persia, who called it “mountain of Light”, now kept in Tower of London 7) Shah, 88.70 carats, now kept in the Kremlin, Moscow.
1) Dresden, 41 carats, kept in Green Hall in Dresden 2) Hope, 45.52 carats, since 1958 is kept in the Smithsonian Institution, Washington, D.C. 3) Star of Africa, 530.20 carats, largest cut diamond, kept in Tower of London 4) Sancy, 55 carats, since 1906 belonging to the Astor family, Londin 5) Tiffany, 128.51 carats 6) koh-i-noor, 108.92 carats, bought 1739 by the Shah of Persia, who called it “mountain of Light”, now kept in Tower of London 7) Shah, 88.70 carats, now kept in the Kremlin, Moscow.
Diamond Gem Sources
Diamonds are found in primary and secondary (such as river gravels) deposits. India and Brazil are the main diamond producers from secondary sources. However in 1871 diamond was discovered in Kimberlite rock in Kimberly mine, South Africa. This, proved that diamond can be extracted from primary sources. Australia is the main producer of diamond from primary sources; other locations include Ghana, Sierra Leone, Zaire, Botswana, Namibia, Russia (Ural Mountains), USA, and Brazil. You can find our interactive map for gemstone of the world Here.
Diamond Gem Enhancement
Diamonds can be enhanced in following several different ways.
1- Irradiation: This is one of the more established ways to treat diamonds. Low quality diamonds are subjected to irradiation, followed by controlled heating, to achieve bright yellows, blur greens, and very dark greens.
2- HPHT: This is the high pressure and high temperature treatment of a diamond to enhance its color. This treatment is considered as permanent.
3- Laser drilling: In this method a laser is used to improve the apparent clarity of the stone.
4- Fracture filling: in this method a glass-like substance fills a surface-reaching inclusion to mask its appearance.
1- Irradiation: This is one of the more established ways to treat diamonds. Low quality diamonds are subjected to irradiation, followed by controlled heating, to achieve bright yellows, blur greens, and very dark greens.
2- HPHT: This is the high pressure and high temperature treatment of a diamond to enhance its color. This treatment is considered as permanent.
3- Laser drilling: In this method a laser is used to improve the apparent clarity of the stone.
4- Fracture filling: in this method a glass-like substance fills a surface-reaching inclusion to mask its appearance.
Diamond Gem Care
Diamond jewellery requires very little care as it is the hardest mineral on earth. Most diamonds can be cleaned using ultrasonic or steam cleaners.
Diamond Gem Basic Properties Table
Chemical Formula | Crystallized Carbon |
---|---|
Color | Colorless, yellow, brown, green, blue, black |
Hardness | 10 on the Mohs scale |
Crystal System | cubic |
Refractive Index | 2.417 to 1.419 |
Cleavage |
Perfect |
Specific Gravity (SG) |
3.52 |
Transparency |
Transparent to opaque |
Lustre | Adamantine |