A Diamond is a mineral made of carbon that is crystallized. In fact a diamond is more than 99.95% pure carbon. The remaining 0.05 percent of the elements often influences the crystal's color and shape. The diamond is also by far the hardest natural substance known to man. Diamonds form between 75 and 120 miles below the earth's surface. Only at these great depths do the necessary temperature and pressure exist to form this unique gem. Diamonds were delivered to the surface by volcanic eruptions. These eruptions occurred over 50 million years ago. Geologists believe that the first delivery occurred more than 2.5 billion years ago. After reaching the surface, some diamonds settled back into their volcanic pipes. Other diamonds were washed hundreds of miles away by floods and rivers. Some diamonds reached the oceans and were washed back onto the beach. The first diamond mines were discovered in India before 500 BC. India has been the world's major supplier of diamonds for over 2,000 years, producing some of the most famous diamonds. Today, India accounts for only a tiny percentage of the world's diamond production. Today's diamond production leaders are currently Australia, Botswana, Russia, South Africa, Zaire and Canada. Before being transformed into a beautiful piece of jewelry, the diamond must undergo several stages.
STAGE 1 - MINING
The diamonds that made it to the surface were forced up volcanically, through kimberlite pipes. A typical pipe mine consists of a large vertical shaft with tunnels running from the main pipe. The deepest mine runs about 3,500 feet down into the earth. More than 200 tons of rock, gravel and sand need to be blasted, crushed and processed to yield just one carat of gem quality diamonds. Finding diamonds and getting them out of the ground may require the use of jet engines to thaw the frozen ground or to endure the sweltering desert heat. Only about 20% of all rough diamonds are suitable for polishing; the rest are used for industrial purposes. Once the rough is found the diamond's journey begins.
STAGE 2 - ROUGH REACHES THE MARKET
A large proportion of the world's rough supply finds its way to De Beers' Central Selling Organization (CSO). The rough the CSO buys is sorted into more than 5,000 different categories. Once the rough is sorted and priced, it is sold to manufacturers at sights. There are ten sights a year, each lasting a week. The chosen few afforded the chance to purchase at these sights are called sight holders. The balance of the world's rough supply is sold to private buyers, and some through private auctions.
STAGE 3 - MANUFACTURING THE DIAMOND
Regardless of the source, all rough eventually finds its way to the cutting centers. Today, the major cutting centers are Antwerp, Israel, Bombay, Johannesburg, and New York. Upon reaching its destination the rough is carefully examined to decide how it should be cut to yield the greatest value. After the stone's shape and size are determined, taking into consideration the rough's shape, as well as the number and position of its internal inclusions, the stone is marked and usually sawed or cleaved.
The stone then goes through a series of cutters who each have their own specialty. Finally the diamond is polished and ready for sale.
STAGE 4 - THE FINAL JOURNEY
After a diamond is manufactured it needs to be sold. For decades diamond manufacturers have sold their cut diamonds to jewelry manufacturers and diamond wholesalers who in turn, sell to jewelry wholesalers and to retail jewelry stores. Today's technology is changing the diamond pipeline. Diamond manufacturers now have a direct link to the final customer.
By learning the 4C's and buying only certified diamonds it is possible to purchase the same quality diamond for a significantly lower price, over the internet.
In the diamond industry, the existence of fluorescence in a diamond (caused by the natural mineral properties of the diamond), has caused many debates and has, in many instances, influenced the pricing of diamonds.
It is common to find that diamonds with colorless grades (D-E-F) or near colorless grades (G-H-I-J) are lower in price when they exhibit fluorescence and faint yellow grades (K-L-M) are higher in price when exhibiting fluorescence.
The "theory" has been that: 1) fluorescence has a negative impact on colorless diamonds (making them appear cloudy) and 2) a positive impact on faint yellows (blue fluorescence supposedly counter-balancing the yellow color and making the diamond appear whiter).
Given the results of a 1997 GIA study on the effect of ultraviolet fluorescence on a diamond's appearance, we tend to toss the first half of that theory out the window and give slightly less credence to the second half.
The GIA study selected a group of similarly graded diamonds with varying degrees of fluorescence to be observed and commented on by study participants. Participants in the study included: trained diamond graders, trade professionals (e.g., jewelers), and average observers (general jewelry buying public).
Here's a quote from the study:
Bottom Line on Fluorescence
Don't let flourescence unduly influence your choice when selecting a diamond.
If industry experts can't agree on the influence of flourescence and constantly split hairs over its effect, we feel it falls into the range of minutiae that simply serves to confound and confuse, rather than inform the diamond buying public.
However, because of industry debate and prejudice (which appears unfounded), you may find colorless or near-colorless diamonds that exhibit fluorescence have slightly lower prices than those that do not. Our opinion? Enjoy the lower price.
Of course, if you are buying diamonds as an investment and intend resale, you'll want to pay attention to how the industry prices diamonds with fluoresence -- independent of whether the price difference is justified.
STAGE 1 - MINING
The diamonds that made it to the surface were forced up volcanically, through kimberlite pipes. A typical pipe mine consists of a large vertical shaft with tunnels running from the main pipe. The deepest mine runs about 3,500 feet down into the earth. More than 200 tons of rock, gravel and sand need to be blasted, crushed and processed to yield just one carat of gem quality diamonds. Finding diamonds and getting them out of the ground may require the use of jet engines to thaw the frozen ground or to endure the sweltering desert heat. Only about 20% of all rough diamonds are suitable for polishing; the rest are used for industrial purposes. Once the rough is found the diamond's journey begins.
STAGE 2 - ROUGH REACHES THE MARKET
A large proportion of the world's rough supply finds its way to De Beers' Central Selling Organization (CSO). The rough the CSO buys is sorted into more than 5,000 different categories. Once the rough is sorted and priced, it is sold to manufacturers at sights. There are ten sights a year, each lasting a week. The chosen few afforded the chance to purchase at these sights are called sight holders. The balance of the world's rough supply is sold to private buyers, and some through private auctions.
STAGE 3 - MANUFACTURING THE DIAMOND
Regardless of the source, all rough eventually finds its way to the cutting centers. Today, the major cutting centers are Antwerp, Israel, Bombay, Johannesburg, and New York. Upon reaching its destination the rough is carefully examined to decide how it should be cut to yield the greatest value. After the stone's shape and size are determined, taking into consideration the rough's shape, as well as the number and position of its internal inclusions, the stone is marked and usually sawed or cleaved.
The stone then goes through a series of cutters who each have their own specialty. Finally the diamond is polished and ready for sale.
STAGE 4 - THE FINAL JOURNEY
After a diamond is manufactured it needs to be sold. For decades diamond manufacturers have sold their cut diamonds to jewelry manufacturers and diamond wholesalers who in turn, sell to jewelry wholesalers and to retail jewelry stores. Today's technology is changing the diamond pipeline. Diamond manufacturers now have a direct link to the final customer.
By learning the 4C's and buying only certified diamonds it is possible to purchase the same quality diamond for a significantly lower price, over the internet.
Diamond Fluorescence
When we speak of Diamond Fluorescence, we are referring to the diamonds tendency to emit a soft colored glow when subjected to ultraviolet light (such as a "black light").
Before going into the details of fluorescence, here's our overall opinion: the simple existence or absence of fluorescence should not influence your decision to purchase a diamond.  Diamond Fluorescence is a hotly debated topic in the diamond industry, but a 1997 study by the GIA suggests fluorescence makes very little difference to the appearance of the diamond. |
In the diamond industry, the existence of fluorescence in a diamond (caused by the natural mineral properties of the diamond), has caused many debates and has, in many instances, influenced the pricing of diamonds.
 Natural Light |  UV Light |
| Simulated fluorescence | |
The "theory" has been that: 1) fluorescence has a negative impact on colorless diamonds (making them appear cloudy) and 2) a positive impact on faint yellows (blue fluorescence supposedly counter-balancing the yellow color and making the diamond appear whiter).
Given the results of a 1997 GIA study on the effect of ultraviolet fluorescence on a diamond's appearance, we tend to toss the first half of that theory out the window and give slightly less credence to the second half.
The GIA study selected a group of similarly graded diamonds with varying degrees of fluorescence to be observed and commented on by study participants. Participants in the study included: trained diamond graders, trade professionals (e.g., jewelers), and average observers (general jewelry buying public).
Here's a quote from the study:
"For the average observer, meant to represent the jewelry buying public, no systematic effects of fluorescence were detected. Even the experienced observers did not consistently agree on the effects of fluorescence from one stone to the next. "In general, the results revealed that strongly blue fluorescent diamonds were perceived to have a better color appearance when viewed table-up [ed: right-side up, as when placed in a setting] with no discernible trend table-down [ed: upside-down]. Most observers saw no relationship between fluorescence and transparency."In other words, for the average observer fluorescence made no difference and experienced observers (diamond graders and trade professional) did not agree on the influence of fluorescence. And contrary to previous theories, the experienced/trained observers most consistently determined that diamonds with strong fluorescence were the ones with the best color.
Bottom Line on Fluorescence
Don't let flourescence unduly influence your choice when selecting a diamond.
If industry experts can't agree on the influence of flourescence and constantly split hairs over its effect, we feel it falls into the range of minutiae that simply serves to confound and confuse, rather than inform the diamond buying public.
However, because of industry debate and prejudice (which appears unfounded), you may find colorless or near-colorless diamonds that exhibit fluorescence have slightly lower prices than those that do not. Our opinion? Enjoy the lower price.
Of course, if you are buying diamonds as an investment and intend resale, you'll want to pay attention to how the industry prices diamonds with fluoresence -- independent of whether the price difference is justified.
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