What is the history of diamond treatment?
From the earliest, most basic paints and coatings to the most sophisticated high-pressure, high-temperature (HPHT) annealing processes, the history of diamond treatments paral- lels that of human advancement, as one technologi- cal development after another was called upon to serve the “King of Gems” (figure 1).
Can modern treatments really improve a diamond’s appearance?
Some modern treatments, though, have a significant drawback: they can improve a diamond’s appearance, but may not be permanent.
What is the most famous treated-color diamond?
The Deepdene diamond (currently 104.53 ct), which was irradiated and heated in 1955 to intensify its yellow hue, is perhaps the most famous treated-color diamond in the world. Photo courtesy of Christie’s. HISTORY OFDIAMONDTREATMENTSGEMS& GEMOLOGYSPRING200841
What is km treatment for diamonds?
The first, referred to as KM treatment(KM stands for kiduah meyuhad, or “special drill” in Hebrew), opened channels from dark inclusions to the surface not by burning through the diamond but rather by using the focused heat of the laser to expand (or even cre- ate) feathers around the inclusion (McClure et al., 2000; Horikawa et al., 2001).
Which factor normally counts most in setting a diamonds clarity grade?
The face-up view normally counts most in setting the grade because that's how the diamond is seen when it's set in jewelry. In most cases you should tell the customer the diamond's clarity grade and explain it.
Which setting style protects the diamond with a metal collar that wraps around it?
A bezel setting uses a kind of elevated collar that wraps the rim of a gemstone or diamond with a complete metal edge. This type of setting protects a gem better than other kinds of settings. Metal is wrapped around the stone's girdle, leaving only its table and crown visible.
Which of the 4 C's is almost always the top factor in a diamond's beauty?
Of the 4Cs, cut- its proportion and symmetry- is the most important factor in determining a diamond's beauty, value, and light performance.
How precisely opposite sides of the diamond match is considered when judging the cut quality factor of?
The main concern with cut symmetry is how precisely opposite sides of the diamond match. This is judged from dif- ferent views – crown, pavilion, and profile. Another consider- ation is the precision of facet shape and placement.
How many first time brides receive a diamond engagement ring?
In the US, more than 70 per cent of brides acquire a diamond engagement ring; in China it's less than half, but that proportion has been growing rapidly, especially in large cities.
Do bezel set diamonds fall out?
Bezel settings are significantly more secure than their prong-set cousins. Bezel set diamonds will not chip or come loose with wear. If you hit your prong-set solitaire on the edge of a glass desk or marble counter, there's some risk that your diamond could come loose or chip.
What is 4C diamond?
The 4Cs—color, clarity, cut and carat weight—are the globally accepted standards for assessing the quality of a diamond. A diamond's quality depends on a combination of all the four Cs. However, Tiffany & Co. believes the most critical of these is diamond cut.
Which diamond C is most important?
cutOut of the 4 C's of diamonds, the cut of the diamond is the most important. This is followed by color, clarity, and carat weight.
Is VS1 or VS2 better?
A VS1 diamond has no visible inclusions and under 10x magnification, the inclusions are almost unidentifiable. These diamonds make up the top 5 percent of all gem-quality stones. VS2 diamonds will only have eye-visible inclusions 5 percent or less of the time, which are more common in stones over 1 carat.
What is the highest possible clarity grade?
FlawlessFL (or Flawless) is the highest grade for clarity. An FL diamond has no imperfections even when magnified 10x by a professional. For color, D or completely colorless diamond is the highest grade. While flawless and colorless diamonds are extremely rare, cut determines a diamond's true value.
When they formed how many gem quality diamond crystals grew large enough to yield a high quality finished diamond weighing 1 carat or more?
One gem quality diamond crystal in a thousandOne gem quality diamond crystal in a thousand grew large enough to yield a high quality finished diamond weighing 1 carat or more.
What percentage of gem quality diamonds are flawless?
Inclusions and blemishes aren't visible on flawless diamonds, even under 10x magnification. Less than 1% of all diamonds are FL clarity. A flawless diamond is incredibly rare because it's nearly impossible to find a diamond 100% free of inclusions. Six percent of customers buy FL diamonds.
What is a fishtail setting?
Fishtail setting: an elegant setting where the diamond melee is set low into the metal with delicate fishtail-shaped cuts. Flush setting: a sleek setting style in which diamond melee is set individually, directly into the metal and without prongs.
What metals do they set diamonds in?
Gold: The versatile choice for diamond rings Copper, silver, zinc, nickel and other substances are used in the alloy to lend durability and strength to gold. The percentage and type of metals combined in the alloys with gold determine the color and shade that would be imparted to the diamond ring.
What metal is best for diamond?
For a clear and more colorless shine, go with a white metal like platinum, palladium, or white gold. Bright metals will bring out the diamond's fire without overpowering or altering the hue. However, yellow gold is the tried and true standard if you want to warm up your diamond for a classic look.
What are diamonds set in?
The term diamond setting refers to how the stone is fixed to the rest of the ring. In the popular prong setting, the gem sits in a metal cup called a collet, which is soldered to the band of the ring. The stone is then held in place by prongs (also called a claw or a basket), which are bent to hold it firmly in place.
When were diamonds first synthesized?
Diamonds were first synthesized from graphite in the 1950s by the HPHT process. In the mid-1980s, the process was modified to create diamond film. Later, chemical vapor disposition (CVD) improved diamond film production.
Who uses HPHT?
At least six companies from the US, China, Japan, and Russia began using the HPHT process. Because of the fiscal impact of this treatment on the trade, several major laboratories began examining the treated stones.
Why is glass injected into diamonds?
A glass-like substance is injected into the fracture to make it less visible and to improve the stone’s apparent clarity. Because the filling may be damaged or removed during routine cleaning and repair, the technique is controversial in diamond treatment.
What is the color of a 6.61 ct diamond?
Left, prior to annealing, this diamond’s color was considered fancy yellow brown. Right, after annealing, this diamond’s color grade is “L” (faint yellow).
What does HPHT mean in diamonds?
HPHT stands for a high-pressure, high-temperature. This treatment is an effective tool for changing the color of certain diamonds, making them colorless, pink, blue, green, yellowish green, or yellow. Outside of a well-equipped grading laboratory, this form of diamond treatment is virtually undetectable.
Does diamond treatment affect the value of a diamond?
While diamond treatments can increase a stone’s Color or Clarity, the presence of such enhancements may affect the diamond’s value – particularly if the price reflects its appearance after treatment.
Does GIA report diamonds?
GIA will issue reports for treated diamonds that have been laser drilled or HPHT processed, disclosing the presence of treatments on the report. As a further precaution, GIA also laser-inscribes the girdles of diamonds it identifies to be color treated. HOW TO CHOOSE A DIAMOND.