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How is gold graded?

Gold is a highly malleable metal and in its purest form, gold cannot be used to make any jewelery. Hence a small amount of other metals like nickel, silver and copper have to be added to gold to use it. The additives also impart their color to the gold. If copper is added to the gold, then the gold gets a reddish tint. Many people have allergic reaction to Nickel. So if you think you have allergic reaction to gold, think again. Depending on how much alloy is added the gold is graded accordingly. Gold in its purest form is 24 Karat. All jewelery in North America is typically marked with Karat grade. Jewelery made in Italy is marked with fineness such as 417, 583 etc. Here's a chart with the information on the grades of gold.

Ten-karat gold is the lowest grade that can be sold in the United States as "gold," according to Federal Trade Commission regulations. Ten-karat gold jewelery generally is considerably less expensive than its 18K or 14K counterparts, and will resist regular wear and tear. Most Indian jewelery is 22K.

Gold Plate: The term "10K gold plate," on the other hand, refers to a layer of that grade of gold that is bonded to the outside of jewelry made from a different metal. Gold-plated jewelry often has a bright gold color, but sooner or later, the gold plate will wear off.

Vermeil: Recently, jewelry made from vermeil has enjoyed a surge of popularity. Vermeil issterling silver, which is 92.5 percent pure silver, overlaid with gold plating. French jewelry makers invented the process in the 1700s and the product was instantly popular. Again, the minimum fineness of the gold used in vermeil can be no lower than 10K in the U.S.

Shopping for Gold: The FTC does not require that gold jewelry carry a stamp, or imprint, delineating its karat grade, but reputable jewelry makers stamp their products anyway. The stamp will be tiny and in an inconspicuous place, so you may have to search for it, but it's well worth the effort to have that assurance. If you can't find a stamp, ask the vendor to provide you documentation of the grade of gold in the merchandise.

India was the first country to mine diamonds, with some mines dating back to 296 BC. India traded the diamonds, realizing their valuable qualities. Historically, diamonds have been given to retain or regain a lover’s or ruler’s lost favor, as symbols of tribute, or as an expression of fidelity.

A diamond is judged by 4 Cs or carat, cut, color, and clarity.

Diamond Carat Weight

A carat (ct.) is the unit of measurement specifically used to describe the weight of a diamond (or other gemstones). Its name comes from the carob seed – a small seed with a typically uniform weight that early gem traders used as counterweights for balancing their scales, according to the GIA. A single carat is equivalent to 0.2 grams, or 200 milligrams, and is divided into 100 points.

AA certified diamond that comes with a grading report will indicate the exact carat weight to the nearest hundredth of a carat, in decimal format. A 1-carat diamond has 100 points (1.00) while a ¾ carat stone has 75 points (0.75).

Carat weight in pre-set jewelry is typically described as a fraction (e.g. ¾ carats) and has an equivalent decimal range (¾ carats = 0.69 – 0.82 points). A 10% variance is allowed when describing the carat weight in pre-set jewelry.

Diamond Cut

When people talk about “brilliance,” they are referring to the amount of light a diamond reflects. When light enters the diamond, it is refracted and bounces back out in a rainbow of colors.

The way a diamond is cut will have the biggest effect on how the stone catches and interacts with light. It is the ultimate expression of a craftsman's skill in transforming a ro

ugh diamond into a breathtaking gem. If the diamond is too shallow and not cut right, some of the light will be lost out of the bottom. One that is cut too deeply will lose light out the side of its base. An Ideal Cut diamond will reflect most of the light through their table or top surface. The Effect of Cut Quality on Light Refraction

There are many types of diamond cuts, like brilliant, princess, rose, step, mixed, etc. The most popular among them are round brilliant cuts, followed by the princess cut. The characteristic features of a princess cut diamond include its square shape and the four pointed corners. A princess cut diamond displays the same brilliance as that of a brilliant cut diamond, hence it is also known as ' square modified brilliant'. It is said that princess cut has the best features of both round and square cut diamonds. Princess cut diamonds display the same degree of light return as that of a brilliant cut, but have a square shape. They are the most sought-after cut after brilliant round cut.

A princess-cut retains 80% of the rough diamond while a round cut retains only 50%. A rough diamond, mostly in the shape of octahedron crystals (like two pyramids joined together on the base) is used for making two princess cut diamonds, instead of one diamond in other cuts. This again means very less wastage of the original rough stone.

The light return in princess cut diamonds is more than that of the ordinary square-cut diamonds, as they have tent-like facets and vertically angled crown. It is always better to avoid those princess cut diamonds which have very large facets and shallow crown heights. These diamonds are graded for light return by Accredited Gem Appraisers (AGA), American Gem Society Laboratory (AGSL) and European Gem Laboratories - USA (EGL-USA). According to AGSL a cut grade of '0' is considered as the highest grade and as per the AGA and the EGL, 'EX' is the highest grade.

People often mistakenly assume that a diamond’s size is synonymous with its weight, though that’s not necessarily true. The way a diamond is cut can actually obscure its size and true weight. The following diagram shows the relative size of carat weights for a diamond that is cut to the same proportions:

Diamond Color

“Colorless” or “white” diamonds are evaluated on a color-grading scale developed by the GIA. It spans the alphabet from D to Z with D being colorless, and Z representing a light yellow tint. With colorless diamonds, the value is placed on how little color you can see, and this is determined by studying the diamond under controlled lighting and comparing it to the GIA's color scale. Incidentally, D-grade diamonds – that is, truly colorless diamonds – are extremely rare and valuable.

GIA Color Range

Diamonds with a color grade of D, E or F are considered colorless.

Diamonds graded G, H, I and J are near colorless.

Diamonds that fall in the K-M color grade range have a faint yellow tint. Diamonds in the N-R range have a very light yellow tint and S-Z are light yellow.

Diamond Color Scheme

Diamond Clarity

Diamonds are chemically carbon that transform under great pressure. The extreme heat and pressure that diamonds undergo can cause unique “birthmarks” that affect their clarity. These are referred to as inclusions when they are internal or blemishes when they appear on the diamond’s surface.

The independent grading report that comes with every diamond we sell shows a diagram indicating the characteristics of your diamond, including any inclusions or blemishes your diamond may have and where they appear. The most important thing to remember when it comes to clarity is that a diamond's inclusions and blemishes should not be noticeable to the naked eye, nor should they be so excessive that they affect the diamond's durability.

We grade a diamond’s clarity according to the GIA International Diamond Grading System. The GIA Clarity Scale has a range of 11 grades that run from flawless (FL) to obvious inclusions (I3). A diamond that is higher up on the Clarity Scale will be more brilliant – and with all other characteristics being equal, more valuable – because it doesn’t have inclusions and/or blemishes that impede its ability to refract and reflect light.

Clarity Grading Scale

GRADE

DESCRIPTION

F: Flawless. The diamond shows no inclusions or blemishes of any sort under 10X magnification when observed by an experienced grader. Note: Truly flawless or internally flawless (F or IF on the GIA's grading scale) diamonds are extremely rare.

IF: Internally Flawless. The diamond has no inclusions when examined by an experienced grader using 10X magnification, but will have some minor blemishes.

VVS1,VVS2: Very, Very slightly included. The diamond contains minute inclusions that are difficult even for experienced graders to see under 10X magnification.

VS1, VS2: Very slightly included. The diamond contains minute inclusions such as small crystals, clouds or feathers when observed with effort under 10X magnification.

SI1, SI2: Slightly included. Inclusions are obvious under 10x magnification and may or may not be visible to the naked eye. However, when set in jewelry, the inclusions may become less visible.

I1, I2, I3: Included. Inclusions are obvious under 10x magnification and are usually visible to the naked eye. This quality allows for a larger diamond to be purchased at a lower price.

A certified diamond's quality is guaranteed, and this makes it more valuable than an un-certified stone. The certificate verifies a diamond’s identity and value, and it will be recognized by all gemologists.