Saturday, April 25, 2009

Blue

A fluorine aluminium silicate that comes in yellow, yellow-brown, honey-yellow, flax, brown, green, blue, light blue, red and pink ... and sometimes it has no color at all. The name "topaz" is derived from the Greek Word tòpazi[òs].
14K White Gold Ring with Radiant Blue Topaz and Diamond Accents, Blue Topaz
Known for at least 2000 years and is one of the gemstones which form the foundations of the twelve gates to the Holy City of the New Jerusalem. These so-called apocalyptic stones are intended to serve in protection against enemies and as a symbol of beauty and splendour. It cannot be proved conclusively whether the name of the topaz comes from the Sanskrit or the Greek, though the Greek name 'topazos' means 'green gemstone'. The Romans dedicated the topaz to Jupiter. The colour in which the topaz is most commonly found is yellow, and that is the colour in which it occurs in one of the major German gemstone rocks, the Schneckenstein (a topaz-bearing rock said to resemble a snail) in Saxony. In the 18th century, it was mined there during a period of over 60 years. However, most of the crystals were hardly a centimetre in diameter. You had to go to Siberia or Brazil to find crystals as large as your fist. Having said that, anyone who is interested can convince himself of the beauty of cut specimens in the topaz set in Dresden's Grünes Gewölbe (Green Vault). The enormous and magnificent topaz from the Portuguese crown, the Braganza, was for a long time thought to be a diamond. It weighs 1680 ct..

International Diamond Grading Laboratories


AGL (American Gemological laboratories, Inc)
Founded in 1977. Tend to specialise in colored diamonds and gems. Reports and verifications
580 Fifth Ave. Suite 706, New York, NY 10036
Tel: (212) 704-0727, Fax (212) 764-7614, email: aglgemlab@aol.com

AIGS (Asian Institute of Gemological Sciences)
Jewelry Trade Center, 6th Floor, 919 Silom Rd
Bangkok 10500, Thailand
Website: AIGS
Tel: (662) 267-4325/7, Fax: (662) 267-4327

AGSL (American Gem Society Laboratories)
These are for the Trade only
8917 W. Sahara Ave., Las Vegas, NV 89117
Website: AGSL
Tel: (702) 255-6500, Fax: (702) 255-7420

CCIP Gemological laboratory (Chambre de commerce et d'Industrie de Paris Laboratory)
Also known as the French Gemological Laboratory
2 Place de la Bourse, 75002 Paris France
Website: CCIP
Tel: (33) 1-40-262545, Fax: (33) 1-40260675

CGL (central Gem Laboratory)
Miyagi building, 5-15-14 Ueno Taito-ku
Tokyo 110-0005, Japan
Website: CGL
Tel: (81) 3 3836-1627, Fax: (81) 3 3836-6861

DEL (Deutch Diamant und Edelsteinlaboratorien Indar-Oberstein)
(German Diamond & Gemstone Laboratories Idar-Oberstein)
Mainzer Str. 34, D-55743 Idar-Oberstein, Germany
Website: DEL
Te;: (49) 6781-981355, Fax (49) 6781-981357

EGL (European Gemological laboratory)
Website:EGL
They have branches in most major diamond capitals including, Antwerp, Johannesburg, Istanbul, London, Tel Aviv and Seoul.

Also there is the EGL USA Group at 6 West 48th Street in New York, NY 10036
Their Tel; (212) 730-7380. Fax: (212) 730-7453
Website: EGL USA
They were founded in 1986 and are independent of the EGL labs in Europe
They have branches in Los Angeles, Vancouver and Toronto also.

GCAL (Gem Certification & Appraisal Lab)
580 Fifth Ave, Lower Lobby
New York, NY 10036
Website: GCAL
Tel: (212) 869-8985. Fax: (212) 869-2315

Gem A (Gemmological Association & Gem Testing Laboratory of Great Britain)
This one was founded way back in 1925 and is for the trade only
27 Greville Street, London, EC1N 8TN, UK
Website: Gem A
Tel: 44-207 404-3334, Fax: 44-207 404-8843

GIA Gem Trade Laboratories Inc
Founded in 1949 and also for trade only
5355 Armada Drive, Carlsbad. CA 92008
Tel: (800) 421-7250 & (760) 603-4500
Also: 580 Fifth Ave., New York, NY 1003.
Tel: (212) 221-5858
Website: GIA

GGL (Gubelin Gem Lab Ltd)
Maihofstrasse 102, CH-6000 Lucerne 9 / Switzerland
Website: GGL
Tel: 41 41-429-1717, Fax: 41 41-429-1734

GIT (Gem & Jewelry Institute of Thailand
Chulalongkorn University, Phayathai University
Phayathai Road, Patumwan,
Bangkok 10330 Thailand
Website: GIT
Tel: (662) 218-5470-4, Fax (662) 218-5474

HRD (Hoge Raad vorr Diamant)
The Belgium HRD was founded in 1976. They also have offices in Hong Kong, The US, The Middle East, Italy and Spain.
Hoveniersraat, 22, B-2018 Antwerp, Belgium
Website: HRD
Tel: (32) 3-222-06-31, Fax (32) 3-222-06-05

IGI (International Gemological Institute)
The IGI was founded in Antwerp in 1975 and is one of the most well known internationally.
There are branches in most of the major diamond capitals including, Bangkok, Dubai, Los Angeles, Mumbai, Seoul, Tel Aviv, Tokyo and Toronto
US address is: 589 Fifth Avenue, New York, NY 10017.
Website: IGI
Tel: (212) 753-7100, Fax (212) 753-7759

PGS (Professional Gem Sciences)
Founded in 1980
5 South Wabash, Suite 1905, Chicago IL. 60603
Website: PGS
Tel: (312) 920-1541, (888) 292-1888, Fax (312) 920-1547

SSEF ( Swiss Foundation for the Research of Gemstones)
Founded in 1974)
Falknerstraase 9, CH-4001, Basel, Switzerland
Website: SSEF
Tel: (41) 61-262-0640, Fax (41) 61-262-0641

Diamond Appraisal Laboratories


G.I.A. The Gemological Institute of America.
GIA is the industry standard for grading.
Certificates provide:

Shape Measurements
Weight
Depth Percentage
Table Percentage
Girdle Thickness
Culet Size
Polish
Symmetry
Clarity Grade
Color Grade
Fluorescence
Comments about Diamond
Plot of Internal and External Inclusions
GIA Grading Certificate

A.G.S. - American Gem Society

The A.G.S. gemological laboratory is equal to or more strict than G.I.A. AGS quality reports are most often used by diamond cutters who wish to confirm near ideal or ideal cut diamonds. The A.G.S. grading laboratory director is Peter Yantzer, past founding director of G.I.A.'s Gem Trade Laboratory. The A.G.S. was founded by Robert Shipley the founder of G.I.A. A.G.S.. Diamond Quality Reports provides this information:

Description Shape and Cut
Weight Measurements
Depth Percentage
Pavilion Depth Percentage
Table Percentage
Crown Angle
Crown Height Percentage
Pavilion Angle
Culet Size
Girdle Thickness
Polish/Symmetry
Clarity Grade
Color Grade
Cut Grade
Fluorescence
Comments about Diamond
Plot of Internal and External Inclusions
HRD Laboratory Hoge Raad voor Diamant
The Diamond High Council:

H.R.D. Certified Diamond Reports provide:
HRD Grading Certificate

Shape and Cut
Measurements
Weight
Proportions
Girdle Percentage
Table Percentage
Crown Percentage
Pavilion Percentage
Girdle Thickness
Culet Size
Finish
Clarity Grade
Color Grade
Fluorescence
Comments about Diamond
Plot of Internal and External Inclusions
E.G.L. - The European Gemological Laboratory:

EGL Grading CertificateE.G.L. provides a detail diamond report. The E.G.L. certification does provide more proportion information than the G.I.A. diamond report by including the important pavilion and crown angles in their diamond report. Be aware that plots of internal and external blemishes on E.G.L. certifications are much less detailed than G.I.A. or A.G.S. quality reports. Many diamonds under one carat in size are certified by E.G.L. due to the benefit of lower cost and faster service. E.G.L. also provides a economically priced miniature version of its full certification. E.G.L. Certified Diamond Reports provide this information:

Shape and Cut Measurements
Weight
Depth Percentage
Table Percentage
Crown Angle
Pavilion Angle
Girdle Thickness
Culet Size
Polish
Symmetry
Clarity Grade
Color Grade
Fluorescence
Comments about Diamond
Plot of Internal and External Inclusions
Here are some Appraisal Abbreviations

Diamond Appraisal


When it comes to the price of diamonds it is important to know the value of a diamond. So if you want to buy a diamond an appraisal is vital to ensure you fully understand the value of your diamond. Most diamonds are sold retail with a heavy mark up, especially from department stores, and the true cost of diamonds is considerably less than the retail value. Often 50 percent or more.

What is Diamond Appraisal
No two diamonds are ever alike. Each have their own characteristics. A diamond appraisal is where a properly qualified gemmological laboratory studies your diamond and gives you a report that lists all the qualities of that particular diamond A diamond should be properly appraised and a certificate should be issued giving the details of that appraisal. When you come to sell that diamond, having a properly authenticated appraisal by an established appraiser can make a big difference with the sale.

Some points to take note of when having your diamond appraised.

Seek out an established appraiser. Some people have gotten an appraisal from a department store or the store where they purchased the diamond. This would not guarantee you an proper appraisal. More like a promotional for that store.

The appraiser should be independent and at least a member of the National Association of Jewelry Appraisers.

What the Appraisal Consists of
The appraisal should consist of the exact and specific details about the diamond. This should include:

Weight. Diamonds are weighed in carats. A carat is .2 grams. A gram of diamond would be a massive 5 carats. Very large in diamond terms although the actual diamond is small. A carat is further divided into Points, and there are 100 Points to a carat. So 1 point is .002 of a gram. Very small indeed. Shape and Cut. What is the shape and cut of the diamonds There are various different established cuts.

The proportions of the diamond should be shown including the:

Depth
Table
Crown
Pavilion
Girdle

The culet. This is a point on the bottom of a diamond's pavilion and it is called a culet (pronounced que-let or the French sounding que-lay). Very often the culet is polished as a flat facet to prevent chipping. More often these days the cutter will "close" this facet to a point. Here would describe the type of culet for this particular diamond

Also what is the finish. The quality of the polish and symmetry. These should be graded as GOOD or above.

The Clarity Grade should be clearly listed also. Check the clarity chart here Diamond Clarity.

The color grade should also be shown and lastly any additional comments that might be relevant for the diamond. Here is a list of the color grades. Diamond Color

A diagram of the diamond showing any flaws should also be included and the date of the appraisal should be shown also.

Some appraisal abbreviations are shown here Diamond Appraisal Abbreviations

Some appraisors can be found Diamond Appraisors.

Buy Diamonds
Interestingly enough buying diamonds online can be a better buy than from say Sears, for example. The mark up is considerably less as one does not have to contribute to the bright lights, fine store fittings and employees wandering around not to mention the management and shareholders �cut�. However it is vital in this situation that you get a proper appraisal with the diamond as you are buying "blind" as it were. You cannot see the diamond before you buy, only a picture on your screen.

An independent appraiser is worth his weight in gold when it comes to appraising the price of a diamond. the cost also especially when it comes to insurance.

The details of the stone should be recorded along with the value and other details that identify the stone in the event it becomes stolen.

Diamond appraisal, therefore, is not just a idle fancy but a necessary and important step to safeguarding the price of your diamonds.

Picture courtesy of International Gemological Instititue

Carat Weight


Diamonds are the heaviest and densest material known to man. Diamonds are weighed in carats. A carat is .2 grams. A gram of diamond would be a massive 5 carats. Very large in diamond terms although the actual diamond is small.

A carat is further divided into Points, and there are 100 Points to a carat. So 1 point is .002 of a gram. Very small indeed.

There is a scale of weight for Diamonds and this is shown here:

Weight Size (diameter) Weight: pts (diameter) Weight: fractions
0.10ct 3.00mm 10pts 1/10th
0.20ct 3.85mm 20pts 1/5th
0.05ct 1.00mm 5pts 1/20th
0.25ct 4.10mm 25pts 1/4th
0.33ct 4.55mm 33pts 1/3th
0.40ct 4.80mm 40pts 4/10ths
0.50ct 45.15mm 50pts 1/2th
0.66ct 5.72mm 66pts 2/3th
0.75ct 6.00mm 75pts 23/4th
0.90ct 6.40mm 90pts 9/10ths
1.00ct 6.65mm 100pts 1 carat
1.50ct 7.50mm 150pts 1&1/2 carats
2.00ct 8.10mm 200pts 2 carats

Due to the minute differences in the weight of most diamonds they should always be accurately weighed on an electronic scale to the nearest 1000th of a carat (.001). Stones are always rounded up or down to the nearest 1000th of a carat by the way.

The other factor to consider with weight is a certificate. Where a diamond has been assessed and weighed at a laboratory, a certificate should be issued to confirm the assessment. No stones should ever be purchased without a certificate from a bona fide laboratory.

Code Laboratory
ADL Antwerp Diamond Laboratory
AGAAmerican Gem Apraisal Laboratories
CIBCIBJO (Europe)
CSAJewellery Council of South Africa
DGLDiamond Grading Laboratories (London)
EGIEuropean Gemmological Institute (Antwerp)
EGLEuropean Gemmological Institute (Antwerp & London)
PNFP N Ferstenberg Pbv A
GAGGesellschaft fur Angewandte Gemmologie
GANGemological Institute of Antwerp
GIAGemological Institute of America
GIINational Gemological Institue of Israel
GILGem Information Laboratory
GTLGem Testing Laboratory of Great Britain
NGLNorthern Gemmological Laboratories (UK)
HRDDiamond High Council (Antwerp)
HRGHeinz R Gartner, DGemG, FGA (Germany)
IGIInternational Gemmological Institute (Antwerp)
PSLPrecious Stone Laboratory (London)
VPTVerena Pagel-Theisen, DGemG FGA (Germany)
WGWerner Galia, DGem, (Germany)

A complete list of laboratories with address and contact numbers is available at Lab List

It cannot be iterated enough to ensure that all diamonds you buy should have a certificate from one of the above laboratories.

See also Diamond Appraisal

Diamond Clarity


Clarity is the term given to indicate the purity of a diamond. Most diamonds have minute imperfections and the clarity is the way of grading the purity depending on the number of imperfections the diamond has or does not have.

Diamond Clarity Terms
The diamond industry uses the term "internal characteristics" instead of "inclusions". For natural diamonds, the "internal characteristics" in the diamond are growth crystals that give the diamond its character and unique fingerprint. Laboratory made diamonds are somewhat different and usually contain no inclusions.

Diamond Inclusions. These are imperfections, or flaws, inside the diamond.
Tiny spots of white, black, or other colors.
Cracks. You can get cracks in diamonds, some cause no problems at all. Others can cause the stone to split.
Colored and uncolored crystals.
Diamond Blemishes.
Flaws on a diamond's exterior surface.
Many exterior flaws are the result of poor cutting and polishing process.

Basic diamond terms can also be found at Diamond Glossary

How Diamond Clarity is Graded
GIA clarity grading is generally done under 10x magnification with darkfield illumination. The GIA Gem Trade Laboratory, uses a binocular stereo microscope as standard equipment, able to zoom to higher magnifications when required.

These microscopes are equipped with darkfield illumination, as well as an ultraviolet light filtered overhead light. When grading is performed using a 10x handheld loupe, "darkfield" illumination is more difficult to achieve. The grader must use a light source in such a way that the base of the stone is lit from the side, and the crown of the stone is shielded from the light.

After the diamonds is thoroughly cleaned, the diamond is gently picked up using tweezers in a girdle-to-girdle hold. The grader views the diamond for the first time through the table, studying the culet area of the stone for inclusions. The diamond is then set down, and picked up with the tweezers in a table-to-culet hold. In this position the diamond can be studied from the pavilion side, and the crown side, examining the diamond through each facet for inclusions.

Once a sector of the diamond has been thoroughly examined the grader rotates the diamond using the tweezers, so that the neighboring sector can then be examined. The grader uses darkfield lighting (This is secondary light that has reflected off other objects rather than using a direct light source) to reveal characteristics, and alternatives to reflected, overhead lighting to find out if a characteristic lies either within the stone or on the stones surface, or both.

If the grader is using a stereo microscope, they may zoom in to a higher magnification to make closer observations of an inclusion, but then return to 10x magnification to make an assessment of it's impact on the clarity grade.

If a stereo binocular microscope has been used, a final assessment using a 10x loupe is performed before the final judgment is made on the clarity of the stone. The grader firstly decides the clarity category of the diamond using the keywords; none (FL, or IF if blemished), minute (VVS), minor (VS), noticeable (SI), obvious (I). The decision is then made on the grade of the diamond.

Diamond Clarity Grading
The grading scale is as follows:

IF would have no inclusions and be internally flawless, perfect clarity in other words.
Both grades VVS1 and VVS2 would be very very small inclusions, pin pricks in fact.
VS1and VS2 are still very small and difficult to see.
SI1 and SI2 would be tiny but easily seen.
I1 is small and recognisable immediately.
I2 and 13 would have larger and/or numerous inclusions, obvious recognisable immediately
There is also third pique (pronounced peekay) sometimes written as p3.

Any flaws in Diamonds can include external blemishes also from natural causes as well as from poor polishing. Most blemishes and inclusions are small enough to have no or little effect on the beauty of the diamond.

Most inclusions you find diamonds do not affect the diamonds' performance or structural integrity. However, where you get large clouds this can affect a diamond's ability to transmit and scatter light. This reduces the quality and the demand for and so the price of the diamond. Large cracks close to or breaking the surface will reduce a diamond's resistance to fracture also.

Naturally. diamonds with higher clarity grades are more valued, with the exceedingly rare "flawless" graded diamond fetching the highest price. However, minor inclusions or blemishes can be useful, since they may used as identifying particular diamonds rather like a fingerprint.

Also, as synthetic diamond technology improves and distinguishing between natural and synthetic diamonds becomes more difficult, inclusions or blemishes can be used as proof of natural origin.

Diamond Inclusions and Blemishes
The diamond industry uses the term "internal characteristics" instead of "inclusions". For natural diamonds, the "internal characteristics" in the diamond are growth crystals that give the diamond its character and unique fingerprint.

There are several types of inclusions and blemishes, which can affect a diamond's clarity in varying degrees. Also some features resulting from diamond enhancement procedures, such as laser lines, are also considered inclusions and/or blemishes.

Inclusions
Clouds
Feathers
Included crystals or minerals
Knots
Cavities
Cleavage
Bearding
Internal graining

Blemishes
Polish lines
Grain boundaries
Naturals
Scratches
Nicks
Pits
Chip

Diamond Clarity Enhancement
Laser "drilling" involves using a laser to burn a hole to a colored inclusion, followed by acid washing to remove the coloring agent. The clarity grade is the grade after the treatment. The treatment is considered permanent.

GIA, as a matter of policy, does NOT certify clarity-enhanced diamonds. If you see a GIA Diamond Report with the words "clarity enhanced" or "fracture-filled," it is surely a counterfeit report.

Clarity can also be "enhanced" by filling the fracture much like a car windshield crack can be treated. Such diamonds are sometimes called "fracture filled diamonds". If this has been done it should be disclosed and reputable filling companies use filling agents which show a flash of color, commonly orange or pink, when viewed closely. There can be a significant price discount for fracture-filled diamonds.

One important point is that the treatment is not permanent or as long lasting as the diamond and the GIA will not grade fracture-filled diamonds for this reason. Reputable companies often provide for repeat treatments if heat causes damage to the filling. The heat required to cause damage is that of a blowtorch used to work on settings, and it is essential to inform anyone working on a setting if the diamond is fracture-filled, so they can apply cooling agents to the diamond and use greater care while working on it otherwise cracks may appear in the diamond and its value will be heavily reduced.

Diamond Clarity
So diamond clarity is important to consider when buying diamonds. A Diamond with no imperfections or inclusions would be a top grade diamond and would be classified as internally flawless (IF). It would be extremely rare and would command a much higher price than one which has many recognizable imperfections.

But when you read the detailed explanations for each clarity category, you see that the flaws usually cannot be seen by the naked eye without magnification, even by an experienced jeweler.

Most of the tiny imperfections do not affect a diamond's brilliance and it is not until you reach the bottom level of "I" categories that imperfections begin to detract from the beauty and the price of the diamond.

So do not be concerned too much if the clarity of your diamond is not near the top of the scale. Indeed, it can a characteristic that marks your diamond as being very individual and unique.

Buy Diamonds


The cost of buying diamonds can vary considerably depending on the type and quality of the diamond.

Diamonds can vary in price from a few hundred to many hundreds of thouosands of dollars depending upon the quality and the size of the diamond. the larger the diamond and the better the quality the more per carat they will cost.

You want to get the best diamond for your money so it is a good idea to have some idea of what the qualities of a diamond are and how they affect the price.

Here are some useful hints you can use to buy diamonds.

Types of Diamonds
There are many types of diamonds. The Cut of a diamond is the best way to recognize types of diamonds This is the shape of a diamond and the final presentation bu the diamond cutter. The more common shapes, called Cuts are as follows:

Round Brilliant
Emerald Cut
Princess Cut
Heart Cut
Oval Cut
Marquise Cut
Pear Cut
Round Brilliant

These are shown at the top of the page. Some Cuts are more popular than others and some are more suitable for certain types of jewelry than others. The Princess cut is probably the most poplar of all.

Diamonds are also categorized by their color, clarity and weight. Each plays a part in defining a type of diamond.

How Much are Diamonds
The price of diamonds vary. It is dependent upon the quality of the diamond, determined by the color, clarity and cut, and the carat weight of the diamond, which determines how big the diamond is. So to have an understanding of what price you should pay for a diamond, it is necessary to know what sort and quality of diamond you are buying.

As part of checking the price of the diamond there should be a certificate from an independent gemmological laboratory that lists the true characteristics and qualities of the diamond. This will help to get a accurate valuation of the diamond.

The higher quality diamond the higher will be the price. But also watch for low quality diamonds being sold for high prices. This is why it is so important to have an independent evaluation, especially for a high value diamond.

Where to Buy Diamonds
Buying diamonds online can give you the opportunity of finding the best cut diamonds. It is relatively easy for sellers to list their wholesalers inventories online whereas stores can only offer and show their current stock. This will open the door to a much larger selection of beautifully cut diamonds at the best price. Online dealers, tend to be cheaper than from the local diamond shop in the High Street as they have much lower overheads, no shop, utilities and little staff to pay for.

In addition, as there are many more dealers on line than there are stores, competition is increased and a greater variety of diamonds is made available. There may also be some tax benefits to be derived from buying interstate and even from other countries in many cases.

Browse the dealers online and locate those that are reputable and reliable. Ring them up and discuss how they operate. Read their terms and conditions on the web site. Ensure they have a fixed address and contact numbers and faxes. Check if they are members of a Diamond Association in their country.

Get each purchase independently appraised. This ensures you know what you are getting. It applies even if you are buying a diamond from a store. Especially if you are not experienced in understanding the value of diamonds.

Do a comprehensive search on prices. Once you know what to look for in a diamond you can compare apples with apples, or in this case diamonds with diamonds.

Whether you are buying just the one diamond for a celebratory occasion, or to impress that special person, or collecting as a hobby or for investment purposes, diamond buying can be a satisfying and rewarding experience provided you follow the important points above.

What to look for in Buying a Diamond
Firstly general information about diamonds is offered through the links on the right. the 4 C's of diamonds, cut, color, clarity and carat weight, the basic facts about diamonds, how to tell a real diamond from a imitation or zirconia. There are various addition articles covering the various facets (pun intended) of different diamonds, added on a regular basis so it pays to check back at regular intervals and read all of those as well.

Ensure you educate yourself about diamonds. Understand all about how diamonds are cut. Read the article on the 4C's of diamonds, cut, color, clarity and carat weight. Check out the educational links on the links page.

Tips and Hints
Diamonds look their best in a well lite environment hence the lighting in many stores is deliberately designed to show the diamonds at their best. However when you get the diamond home or in the natural light you would normally display it, the difference can be disappointing.

So there is an additional advantage to buying diamonds online where you can have them shipped to your home and inspect them in the light they would normally be worn. You can also take them to a local jeweller and get an additional assessment prior to confirming your purchase.

Ensure you get a certificate with any diamond you purchase. This is important not only to ensure you get what you pay for but also to establish the insurance value of the diamond and as substantiation when and if the time comes to sell it.

It is important therefore that you educate yourself very well with the various aspects of diamonds that you need to make an informed purchase.

Provided you do some due diligence and understand about diamonds you will be able to buy diamonds with confidence.