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Standardized Pearl Grading

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Old 08-22-2005, 02:40 AM
PearlsAndJade.com PearlsAndJade.com is offline
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At Caitlins suggestion I'l start a thread on Standardizing Pearl Grading.

Use of the current non-standard grading system of A, AA, AAA, etc. is the perfect way for consumers to be bilked. All someone has to do is say my pearls are AAA; they sell for $10,000 in the stores, but I sell them for the unheard of price of ONLY $99.00; and the general bargain hunting non-researching population will think they're getting a steal.

Well, they're being stolen FROM, and some never know it. Typically, the fraudsters will have a high freight charge, and a restocking fee, so that its mostly impractical to return the item, and suing them is too costly, and impossible for the Chinese merchants.

A standardized grading system for pearls, such as exists for diamonds would reduce the amount of fraud that's taking place, and would force eBay to require their sellers to use the system, just as they did with diamonds.

The GIA, recognizing this need, developed a "standard description system". They do not use any letter grade. Their reasoning is that if you describe a pearl on the phone using their method, the two people in the conversation will be talking the same language and both can visualize the same pearl.

It is really a good system, and everyone that has taken the GIA Pearls course recently are familiar with it.

I adoped their system with some modification. My problem was that since everyone else uses the grade system, I felt if I did not use a letter grade then many potential customers would pass my web site on by.

A supplier of mine had a system that used a letter grade with a description that was quite good, but not quite what I thought was required.

Consequently, I took his system and modified it, and incorporated my modified GIA system into it and came up with a grading system that uses the letter grades and the description method.

It grades four value factors (shape, luster, surface, matching) individually. Next I average those 4 grades, giving less weight to "matching" to come up with an average letter grade that the buying public can relate to. On the product page, I give a brief description and grade of the factors, and they can go to my "grading page" to view the full description if they wish.

I have also incorporated detailed photographs into the product description so that between the photos and the descriptions, the customer knows exactly what they're getting, and usually they are pleasantly surprised that the item is better than the description.

Next I designed a grading board using my grading system and asked a supplier to build it for me. He did, and I saw it when I was there last week, but I forgot to bring it with me. He'll ship it with my pearls, and when I get it I'll photograph it and have it on my web site also.

Grading boards are difficult to make. He spent a lot of time gathering the necessary pearls for the board. But they are great for educating employees, or using to compare other pearls before buying.

This system is for freshwater pearls. It may need revising for akoyas, however, my top grade is AAA+. That leaves me room to add an AAAA for any strand that I feel matches the akoya quality.

As a starter in this thread, you can view my grading system at the following link:

http://pearlsandjade.com/c=tsUS8exOs...rgradingsystem

Bill
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Old 08-22-2005, 11:36 AM
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Richard W. Wise Richard W. Wise is offline
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Bill,

Nicely laid out system not too different from Gemology Tools. I notice that your system (thus far) only takes round pearls and strands into consideration.

How would you grade individual pearls for shape, i.e. button, pears, drops, etc. Would you discount anything not round?
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Old 08-22-2005, 01:44 PM
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Caitlin Caitlin is offline
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Thanks Bill!

Hello Richard! Now that I know so many real experts are tuning into this forum, I think there is a real possibility for some education of the public, including me, to happen.

BTW, I am one of the people who uses button and other shapes of pearls a lot. I already know that all the coin and diamond shaped pearls I've used have bead nucleii, but the button pearls are still pristine I believe.

I do not have a standard for the button shape, I just look for best luster and smooth skins and buy by size. But I can see that a discusson of shapes in the standard would be useful. All those bead nuceated coin pearls have only a small percent that is not messy, with tails and rough skins. Finding a quality coin pearl is difficult and fairly expensive!

I know I care about luster first and I like it high.I have deliberately chosen high luster, but slightly off round (up to 12% or so) for far less expensive pearls with the added advantage of the pearls looking more "organic" with the slight variations in roundness. I usually string pearls with other beads and nicer pearls lend a unbeatable touch. I make a lot of strands of button pearls alternating with rondells of amethyst or peridot or garnets. Very sopisticated look for around $40-$60 depending on venue.

Perfection is ok if you can afford it, but the grading of pearls allows everyone into the feeding trough. There is a pearl for everyone!

Last edited by Caitlin; 08-22-2005 at 01:50 PM.
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Old 08-22-2005, 02:37 PM
PearlsAndJade.com PearlsAndJade.com is offline
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Quote:
Originally Posted by Richard W. Wise
Bill,

Nicely laid out system not too different from Gemology Tools. I notice that your system (thus far) only takes round pearls and strands into consideration.

How would you grade individual pearls for shape, i.e. button, pears, drops, etc. Would you discount anything not round?
Hi Richard,

The system is used to grade individual pearls as well as strands, using the three factors of Shape, Luster and Surface. Matching only applies to strands, or perhaps a pair of earrings.

I had not considered that Button should have a category – thanks for pointing that out.

Although, technically, Button is not Symmetrical, it could be placed into the Oval category, as long as the pearl is a true button and not distorted in shape. If the shape were distorted enough, it would drop down into the Semi-Baroque category. Temporarily, I’ve added Button next to Oval.

However, to be more correct, it may be better to add a Category of Button between Symmetrical and Semi-Baroque.

For the time being, I’ve modified the text to show Oval and Button in the Symmetrical category, and will leave it open for discussion purposes to see if it should stay there, or have its own category. All comments on where Button should be placed are appreciated.

Drop and Pear of course have their own category.

Any pearl in the Symmetrical category --Button, potato, rice, drop and pear -- which are graded A, would drop down into the Semi-Baroque category for a grade B, if the shape is distorted enough.

Thanks for your comments

Bill

PS. I looked at your book and it looks interesting. Next spring I hope to have time to take GIA's AJP course, and I'll probably buy your book at that time. I don't have the time to devote to the study right now.
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Old 08-22-2005, 10:36 PM
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jshepherd jshepherd is offline
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I am not sure what you mean by 'a button cannot be symmetrical'.

I think there are a lot of hurdles to a good grading system for pearls. The first, of course, is that it would have to vary from type of pearl. The value factors of a freshwater strand will differ from important value factors of a cultured South Sea or Tahitian strand for example.

Another very difficult hurdle is the education. I spend a lot of time in the jewelry district in Los Angeles as we outsource a lot of our stringing there. In my years of commuting to the city I have become friends with a lot of jewelers. One thing that stands out more than anything else is the lack of pearl knowledge in the jewelry profession. A lot of jewelers cannot even tell the difference between high quality freshwater pearl and an Akoya, or a small Tahitian and a dyed Akoya. Here is a test that I would be willing to bet very few jewelers would pass:
Take a dyed, 9mm Japanese akoya with green overtones to a jeweler. I would be willing to bet 9 out of 10 would grade it as a Tahitian pearl. A pearl professional, however, would never make such a simple mistake.

With all the factors making up a value system for pearls, I do not think a standardized grading system would work well for pearls, unless it grades each facet individually. Even this can cause problems, however, unless the appraiser has a grading board.
Why?

We have all examined pearls in poor light. What do we see? Beautiful, high luster pearls. This is an old Chinese trick. Even comparing the pearls against an actual high-luster strand is difficult without good natural sunlight.

Also, unless the grader is comparing a strand against another, it can be extremely difficult to grade the subtle differences in the luster. This is exactly why, although I have been traveling to Asia purchasing pearls for nearly 10 years now, I still carry sample strands every trip. I would never make a purchase without them.

If a standardized grading system does come into play – one that grades all value aspects of the pearl strand – a grading board with become an absolute necessity. I do not believe even 1% of retail jewelers in the USA would be able to grade pearls without it. The problem is this means having a board for cultured Akoya, freshwater, Tahitian, and South Sea. This would be a large board if we are only grading the rounds. If you factor in the other shapes it becomes an enormous challenge. When buying just Tahitian pearls, for example, the grading is as such:
Round – A, B, C, D (and many farms also incorporate AB, AB- BC, etc.)
Near Round – A, B, C, D
Off Round – A, B, C, D
Semi-Baroque – A, B, C, D
Baroque – A, B, C, D
Circled – A, B, C, D
And of course they always separate nice drops and pear shapes.
This is only based on the size, surface quality, and luster. This does not even factor in the color which is a huge end-consumer value factor.

The GIA currently has a class which teaches students to identify the value characteristics of a strand of pearls. But, this class is only 1 day long, and is an elective. Even if every GIA graduate was required to take the class I still do not believe they would universally be capable of grading pearls. Is the diamond grading class only a day? Or is it more like 3 months of classroom every day?!
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Old 08-25-2005, 11:56 AM
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Richard W. Wise Richard W. Wise is offline
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Jeremy,
Points well made! I have been part of an ongoing discussion of uniform grading systems on another forum. Given all the parameters they are difficult things to construct.

Wondered how you viewed the suggestions made in my book that the outline of the light source (bulb) is a good touchstone for grading luster without samples?

I agree that different pearl species would have to have relatively different standards, that is, in orient (overtone) some species such as Tahitian black (pinctada Margretifera) have it in abundance whereas pearls from the Maxima oyster seem generally devoid of that quality except in the case of very fine examples.
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Old 08-25-2005, 09:30 PM
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jshepherd jshepherd is offline
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The light bulb method definitely can work, but at the same time, in dim light the white pearls will still be more reflective (I like the quote about reading the text on the bulb!). These reflective pearls can look chalky with indirect natural light, but beautiful in the evening. I am not referring to low-end pearls (eBay quality), these will look bad no matter the time of day.
To me the samples I bring are absolutely essential as the difference in high-luster merchandise may be difficult to detect.

One trick I have had to deal with several times over the years (and almost every time with a new factory) is they will not show their high luster pearls, but start with low-quality and then bring in medium quality pearls. With this type of comparison viewing the medium quality pearls tend to look like top quality pearls. This is dangerous for the buyer. With a set of samples this will not/cannot happen.
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Old 08-26-2005, 02:09 PM
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Richard W. Wise Richard W. Wise is offline
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Your point about low light is interesting. I have a sapphire grading stone in a ring I often wear.

The technique used by our Chinese friend is known as "washing the eyes" I think it originated among the gem dealers in Thailand, but who knows, they are mostly ethnic Chinese.

Richard
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