My Private Jeweler Inc. - Grace Evans, San Diego Private Jeweler

Diamonds - The Four Cs Synthetic and Treated Diamonds History

Because of the significant value embodied in diamonds, it is essential that there be a universal grading system that allows laymen to relate ratings to prices. Thus, in the early 1940’s, the Gemological Institute of America (GIA) originated the 4 C’s and the GIA International Diamond Grading System™. The 4 C’s are Carats, Color, Clarity and Cut.

Footnote: Apples to Apples; Carats to Karats:

Diamonds and other gemstones are weighed in metric carats and 1 metric carat is equal to .2 grams, or about the weight of a paperclip. However, karats are the measure of gold purity with 24 karat meaning 100% gold, 18k meaning 18 parts gold and 6 parts of other metal, 14k meaning 14 parts gold and 10 parts other metal.

CARATS Carats define the weight of diamonds, as in 1 or 2 carats or fractions thereof. Because of the high value of diamonds, they are measured on very accurate scales to the hundred thousandths of a carat and rounded to the next hundredth of a carat. All other factors being equal, two .5 ct diamonds are not as valuable as a 1 ct diamond, as larger sizes command premiums in price. Interestingly enough, all other factors being equal, a 1.95 carat stone typically will sell for a disproportionately large discount than the difference in weight from a 2 carat stone would indicate because consumers want that whole number - even though the weight difference in the stones is impossible to see or notice without a very accurate scale. Carats are referred to as "points": .05 carat is 5 points, .50 carat is 50 points, and 1.00 carat is 100 points.

AAA, AA, A, BBB etc. down to C,

0, 1, 2, 3, etc.,

I, II, III etc.

‘gem blue’, ‘blue white’, etc.

Category	Flawless	Internally Included	Very Very Slightly Included	Very Slightly Included	Slightly Included	Included
Grade	FL	IF	VVS₁, VVS₂	VS_1, VS₂	SI_1, SI₂	I_1, I_2, I₃

Synthetic and Treated Diamonds

Diamonds - A History

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COLOR Early standards for grading diamond color included systems such as:

In order to establish a uniform international standard, in 1931 GIA established a D through Z system. (They started with D to avoid any confusion with the earlier A, B, C system.) The system is based upon comparing a given diamond to a clearly defined range of color on a standardized scale, with D representing colorless down to Z indicating increased degrees of color. It should be noted that grading is done under controlled lighting and specific viewing conditions. While highly trained experts will grade a given stone very close to each other’s rating, laymen and even many in the jewelry trades tend to differ widely in their assessment of color.

CLARITY Virtually all diamonds have unique ‘birthmarks’ - during their formation, they have gained imperfections that can be either internal (inclusions) or blemishes (external) that keep them from being perfect. Inclusions include clouds, feathers, minerals, knots, cavities, cleavage, bearding and internal graining. Blemishes include polish lines, grain boundaries, scratches, nicks, pits, chips and breaks. Ex perts state that under 10x magnification there are no perfect diamonds. Those that come close are extremely rare and their pricing is almost prohibitive. The GIA International Diamond Grading System has six categories and eleven grades and is the industry standard. Note: ‘included’ in the chart below refers to containing ‘inclusions’.

CUT Diamonds and gemstones can be cut and polished into virtually any shape. That being said, a truly unique and very unusual shape, in most instances, will reduce the value of a gemstone as it is not consistent with the cuts that are primarily desired by consumers. Below are the most common shapes.

In many instances, the size and shape of an uncut diamond will strongly influence the shape into which it is cut. This can eliminate or minimize flaws, minimize weight by also maximizing the final carat weight and the cut stone's overall proportions. The proportionate width, height, shape and mathematically correct faces of a diamond strongly influence its ability to reflect light and sparkle.

While shape is a personal preference, it should be understood that overall popularity (or the lack thereof) can influence resale considerations.

IN SUMMARY: When purchasing a diamond, it is both prudent and important to be provided an accurate written assessment of its 4-C’s characteristics. These should be clearly stated on any receipts for payment and appraisals that might be provided to you, and they obviously should be consistent with your understanding of what you are purchasing. You will also find that having this information will be invaluable for insurance purposes.

Having an understanding of the 4 C’s and knowing how various differences in its components can influence value and price can also assist you in gaining a comfort level with your investment in a fine piece of jewelry.

Just as for thousands of years people have been trying to magically turn straw into gold with the wave of a magic wand, there have been many efforts to both make synthetic diamonds and somehow treat natural diamonds to enhance their appearance and value. In the land of fairy tales, Rumpelstiltskin successfully turned straw into gold. We are getting closer to that in real life as increases in technology have favored efforts in the world of diamonds.

General Electric was the first to achieve the production of synthetic diamonds and thereafter others have followed with a variety of methods. For the most part, synthetic diamonds are destined for industrial markets where they are incorporated into cutting blades and tools in order to utilize their natural hardness. Also destined for the industrial markets are the many small diamonds that are the byproduct of the search for natural diamonds, as are the waste materials generated in cutting gemstone quality diamonds.

Somewhat larger synthetic diamonds can also be produced; however, they have found a very limited market among consumers who prefer natural stones and their inherent ability to retain their value. Synthetic stones can readily be identified by a trained eye.

Treatment efforts to improve diamond quality and value include:

Color Enhancement: The application of ultra-thin layers of chemicals or plastic coatings to change a stone’s color. These stones are readily identifiable under magnification.

Irradiation: Exposing a diamond to radiation to influence the color of the stone.

HPHT: High pressure, high temperature laboratory processes to change a stone’s color.

Laser Drilling: A laser drills a hole in a diamond to make contact with and burn away an inclusion; however, the process leaves a hole in the diamond.

Fracture Filling: Drilling to fill white areas (feathers) with a glass like substance. Trained eyes can identify this, and the process has been unstable in cleaning and repair processes.

Prong Placement: Hiding a flaw visible to the naked eye under a prong of the setting.

Synthetic or Natural: When I was designing my wedding ring, my husband suggested that we give some thought to synthetic stones. I dedicated several weeks to gathering data, prices and actually comparing natural with synthetic stones of identical size, side by side. While the same amount of money would buy a larger synthetic stone that could look almost real, it finally came down to my husband asking “Who is going to know the difference?” My answer was a heartfelt response of “I would! I would always know that it was not real!” That helped make the decision because I just couldn’t stand the thought of deceiving people or having to explain that it was not a real diamond. My husband also got comfortable with the decision because he concluded that a real diamond had a greater probability of holding or increasing in value, while a synthetic diamond would always be at the mercy of competing with synthetic diamonds produced with newer and lower cost processes, and therefore not a very good investment. For these same reasons I do not handle or recommend synthetic diamonds.

Diamonds are the hardest natural material known to man. Because of their high value and small size, they have been treasured as the equivalent of currency for thousands of years. Interestingly, my father-in-law who originally went to South Africa as a missionary in the late 1920s and subsequently was involved in a number of businesses there, brought his entire net worth to the US in diamonds in his coat pocket when he moved his family back to the US in 1945.

Diamonds are formed from carbon by extreme pressures and high temperatures occurring 85 to 120 miles beneath the surface in the Earth’s mantle. It is estimated that the Earth’s diamonds were formed between 1 billion and 3.3 billion years ago.

Deep formed rocks and minerals (xenoliths and xenocrysts) that contain diamonds are brought to the Earth’s surface by deep volcanic eruptions of flowing magma that subsequently cools into igneous rock. Diamonds are subsequently found in rock formations, in alluvial soils, and in areas where they have been transported by ancient oceans, rivers, streams, glaciers and the forces of erosion. Interestingly, some asteroid impacts with earth have contained diamonds that have been transported from outer space and not created by the forces of impact.

In the modern era, approximately 50% of natural diamonds originate from Central and South Africa, and within recent years significant deposits have been found in Canada, India, Russia, Brazil and Australia. The US has small deposits in Arkansas, Colorado and Montana. The annual yield of natural diamonds is approximately 26 kilograms (57 pounds) with another approximate 100,000 kilograms (220,000 pounds) being ‘manufactured’, or synthesized as the industry refers to them, with virtually all of the synthesized diamonds being small and used in manufacturing cutting tools that utilize the extreme hardness of diamonds.

For many years, cartels such as the DeBeers Corporation have tightly controlled the sale and distribution of diamonds as a means of creating stable long-term markets and well-defined channels of distribution. Uncut diamonds flow into diamond cutters who cleave the diamonds into shapes and sizes that are intended to maximize the value from an uncut diamond.

While diamonds are extremely hard, they are also very brittle. This means they can be cut (cleaved) into pieces by a hammer blow driving a pointed tool in a precise and pre-determined point on the surface of an uncut diamond. Much planning and x-ray analysis precedes this cutting process, as the transformation from an uncut stone to a cut stone can not only create significant value, but it can also create as much as 50% waste and/or dramatically reduce the value of the remaining stone. In general, cutting strives to work around, eliminate, or minimize inclusions or flaws, while preserving a shape that can ultimately maximize size, beauty and value.

Diamonds can also be cut and polished into desired shapes by a time-consuming process of using diamond studded cutting tools.

Cut diamonds are then concentrated in the World’s major diamond markets that include New York, Tel Aviv and Amsterdam, where they are packed into groupings of stones that are offered to diamond wholesalers who cannot pick and choose but must accept an entire lot of stones that has been offered at a predetermined price. These wholesalers are then part of the distribution channel that sell to the many customers, who in turn buy in smaller quantities and also are more specific as to the specific sizes and qualities of the stones that they wish to purchase.

Thus, when you or loved ones, friends or strangers admire your diamond ring, earrings, bracelets or pendant, they are admiring one of nature’s most beautiful and endearing treasures that came from a hundred or more miles below the surface of the earth more than a billion years ago!!

Diamonds