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EGL亞洲總裁演講題目:鑽石“尚無標準”    

 

作者:Joseph Kuzi                                                                                                                          2010-12-21

EGL亞洲 (EGL Asia) 的擁有人和董事

EGL  :  歐洲寶石實驗室  (比利時安特衛普)    European Gemological Laboratory

 

英譯中:  李承倫 先生

 

鑽石分級的通用標準可使該行業提升至一個新的高度。但是,我們尚未達到該階段。實現這一目標至關重要,因為國際鑽石業內對標準的提述易導致鑽石商和公眾之間的誤解

        如果實現鑽石分級的標準化,會使我們遠遠超出鑽石交易所的範疇,而進入證券交易所,在那我們可自由交易衍生工具、期貨和所有其它可附帶鑽石幣值的票據。許多人擁有這一夢想。一些人還擁有實際的想法,並在計畫未來的一些措施。但與此同時,我們需意識到,我們仍束縛於在當地交易所的內部交易或通過銷售人員、快遞公司和類似參與方進行海外銷售中,進行面對面的實物鑽石交易。甚至鑽石與證書的虛擬貿易(線上交易)都是指的將從門到門和手到手交易的實物鑽石。

        然而,我們瞭解到一些關於已存在一個標準或至少即將存在一個標準的推斷。例如,在2008年,香港寶石學協會 (Gemmological Association of Hong Kong) 出版了一本標題為《香港標準鑽石測試方法》 (Standard Methods for Testing Diamond for Hong Kong) 的藍皮書。該書由眾多著名的寶石學家、學術界人士和當地寶石與珠寶組織的代表編制,意在確定香港鑽石分級的一般標準。但該書是由建議構成,而非具約束力的法律,且僅涵蓋香港,而非全世界。此外,這一概念也難以施行。

        你還可能瞭解到GIA關於標準的論述(但是,就像我們下文將看到的,他們對於使用該詞非常謹慎)。例如,該公司的高級副總裁Tom Moses寫到:“GIA的使命是確保[我們的]國際研究事業中反映公眾對寶石和珠寶的信任。且回想GIA早期的改革,我相信我們將以50多年來為顏色和淨度設定標準的方法,來設定切工品質的標準”。

        事實上,CIBJOWFDB等官方行業組織近期已開始在寶石分級的背景下使用“標準”一詞。這會誤導沒學習過寶石學的公眾,他們易誤認為存在一個標準。而事實上並不存在 --> 至少現在不存在。

 

免責聲明

        讓我們看看某家全球著名機構的寶石證書上所隨附,且所有其它領先實驗室頒發的證書上以相同或類似形式出現的免責聲明:“本報告並不構成保證、估計或評估……實驗室不對與本報告有關的任何事負責或做出保證。”

        你注意到了嗎?似乎沒人認真考慮該免責聲明,即使它出現在寶石證書上,而無可非議地,在缺少寶石分級通用標準的情況下,不可能做出客觀評估或保證其它檢驗的結果將與此相同。

 

顏色分級

        拿一個顏色靠近H級上限,但仍處於H級內的鑽石來舉例。每個寶石實驗室是否都會將該鑽石定為H級,或者我們是否可假設某些實驗室會將其定為G級?進一步深入探討此問題,同一個實驗室內的十個分級員是否都會將該鑽石定為H級,還是即使在同一實驗室,在相同的條件下觀察,有些人會將其定為G級?

        人的肉眼能觀察到的是有限的。大部分人難以區別兩個或甚至三個顏色級別。大部分分級員從兩個主要側邊檢驗鑽石,因為左眼和右眼看事物的方式存在差異。男性與女性看到的顏色存在差異,而在上午和下午觀察的顏色均又不同,且在紐約與紐西蘭或紐卡斯爾又會有不同的感覺。

        繼續探討顏色分級的問題:在《GIA鑽石分級手冊》(GIA Diamond Grading Manual) 131頁,有一段描述檢驗鑽石面朝下時顏色的相關內容,和一段關於檢驗面朝上時顏色的內容。還有一段總結了這兩段,告訴我們“通過結合在兩個位置的感覺來估計顏色級別”。這點明確指出,分級是一個主觀而非客觀的過程。此外,關於根據鑽石面朝上時觀察鑽石(寶石實驗室的習慣)對比鑽石面朝下時(佩戴珠寶的人和別人看此人所佩戴的珠寶時的方式)所看到的顏色而給予顏色分級的相關重量,該段中未做出闡述。為消除任何疑慮,我聲明我在列述這些來自GIA的引文和例子時,並非贊成或反對該知名且重要實驗室所採用的分級方式。我使用這些例子是為了強調,即使是該實驗室,該領域內無可匹敵的全球領導者,都認為目前不存在鑽石分級的標準

 

淨度分級

        我們已對顏色分級進行深入討論。淨度分級範疇內的情況亦如此。鑽石內瑕疵的數量是一個相當客觀的因素。我們可假設,香港、以色列或安特衛普的一名寶石學家將就這點記錄相同結果。但是,在檢驗某個瑕疵的大小和位置時,一名寶石學家可能覺得它極大,而另一名可能認為極小。此外,其中一名可能認為瑕疵的位置極為糟糕,而另一名會認為非常普通,不值得擔憂。因此,相同實驗室內的不同寶石學家可能給予同一顆鑽石不同的淨度級別。這就是每顆鑽石要兩名寶石學家檢查,而在他們存在爭議時請另一人檢查的不成文原因。故而,分級是一個多數人判定的結果。多數人判定不能構成標準。


切工分級

        近來引入了一項新的分級-切工分級。儘管切工有時是加工的同義詞,但我可保證,以色列、印度、美國、比利時、香港或任何其它國家的任何經銷商將表示“切工”指“成型”-如同在獲廣泛認可(此處用“通用”恰當)的4C(重量、顏色、切工和淨度)原始定義中一樣。

        按如今的解釋對切工分級時,存在兩個問題:首先,我們只知道如何對圓鑽的切工分級,圓鑽占目前市面銷售的所有鑽石的50%。在對圓鑽的分級中,我們只知道什麼屬於理想鑽石,而從這個極為有限的定義中,我們提出“公差”一詞-彈性邊緣,擴大定義範圍,以納入鑽石在分級尺規上端的增加數目。所有分級員都能做出明理判斷,任何人都可能正確,而沒人可說,他們更加瞭解該詞,而應只按他們的方式來處理。

 

不同的分級系統

        表1列示了四個領先的淨度分級系統。它們中有的類似,而有的有所不同。表2列示了四個領先的顏色分級系統。我們發現這些不同實驗室之間不存在相似性。某實驗室或國家優先選用某系統並不代表它更為準確,且當然不是一個標準。

1:四個領先的淨度分級系統

GIA

俄羅斯

CIBJO

中國

FL

-

IF

1

IF

LC

VVS1

2-3

VVS1

VVS1

VVS2

3

VVS2

VVS2

VS1

4

VS

VS1

VS2

5-6

VS2

SI1

7

SI

SI1

SI2

7a

SI2

I1

8

P1

P1

I2

9

P2

P2

I3

10

P3

P3

2:四個領先的顏色分級系統

GIA

俄羅斯

CIBJO

中國

D

1

Exceptional + White

D (100)

E

2

Exceptional White

E  (99)

F

3

+Rare White

F  (98)

G

4

Rare White

G  (97)

H

5

White

H  (96)

I

6

Slightly Tinted White

I  (95)

J

7

 

J  (94)

K

8

Tinted White

K  (93)

L

8-1

 

L  (92)

M

8-2

Tinted Color 1

M  (91)

N

8-3

 

N  (90)

O

 

Tinted Color 2

 

P

8-4

 

<N  (<90)

Q

 

Tinted Color 3

 

R

 

 

 

S

 

Tinted Color 4

 

T

8-5

 

 

U-Z

 

 

 

 

系統並非標準

        我認為這兩個例子表明,目前我們可談論一個系統(或更為準確的,多個系統),但並不存在一個標準。正如GIA稱(我再度提到GIA,對此並無問題;其為領先性實驗室):“從1950年代初推出以來,GIAD-Z尺規已被用於將鑽石顏色分級為絕對無色到淺黃色優質拋光鑽石”(John M. KingRon H. GeurtsAl M. GilberstonJames E. Shigley,《寶石與寶石學》(Gems & Gemology)2008年冬)。從中,任何人都可看出,GIA的領導者謹慎地採用了“尺規”一詞,而非“標準”。此外,他們還表示這是領先性系統,而非獨有或唯一的系統。

 

標準的標記

        近期存在某種混亂情況,有人認為如果實驗室擁有ISO 17025,即符合一個標準。然而,ISO國際標準只是指實驗室管理的品質,而非鑽石分級。ISO 17025是為測量實驗室所制定,比寶石實驗室品質管制的公認標準ISO 9001要求更高的管理標準。要求寶石實驗室的管理符合17025標準無疑更好,但是否符合該標準並不意味著作為寶石學家存在任何優勢或缺陷,且並不構成其分級的標準。

 

綜述

        既然有關技術是主觀而非客觀的技術,我們就不能在提述鑽石分級時使用“標準”一詞,因為該詞具誤導性。迄今為止,我們行業內的典型是分級的變化,使貿易處於想像範疇,而非商品。我主張一個真正的標準,但它必須名副其實且成熟。當我們開始將鑽石作為商品來交易時,將是一件可喜的事情,因為那會使鑽石交易提升至一個新的高度。目前,我們尚未實現。

 

No Standardization Yet

by Joseph Kuzi

     Universal standardization in diamond grading may take the industry to new heights. However, we haven’t reached that stage yet. It is important to realize this, as the reference to standards in international diamond forums is liable to create misunderstanding among diamantaires and the general public alike.

     If and when it emerges, standardization of diamond grading is going to take us far beyond the diamond exchange, to the stock exchange, where we can trade derivatives, futures and all those papers that can carry the monetary value of the diamond somewhere over the rainbow. Many dream of this. A few also have practical ideas and are planning measures for the future. But in the meantime, we need to realize that we are still tied to the physical diamond that passes from hand to hand, be it in internal trade within the local exchange or overseas sales through salespeople, courier companies and the like. Even virtual commerce – the online trade of stones and certificates – refers to a real diamond that will be passed from door to door and from hand to hand.

    Nevertheless, we hear implications that a standard already exists or is at least about to exist. In 2008, for example, the Gemmological Association of Hong Kong published a bluebook entitled Standard Methods for Testing Diamond for Hong Kong. Produced by an impressive list of gemologists, academics and representatives of local gem and jewelry organizations, the book was intended to ensure general standards for grading diamonds in Hong Kong. However, it consists of recommendations, not binding law, and it covers only Hong Kong, and not the world. Moreover, even this concept is still far from implementation. 

    You can also hear talk of standardization at the GIA (although, as we'll see later, they are very cautious about using this term). For example, Tom Moses, senior vice-president of the company writes: "GIA's mission of ensuring the public trust in gems and jewelry is reflected in [our] international research undertaking. And reminiscent of GIA's early innovations, I believe we will set the standards for cut quality the way we have set them for color and clarity for more than 50 years".

    Indeed, official industry organizations such as CIBJO and the WFDB have recently begun using the term "standard" in the context of gemological grading. This is somewhat misleading to an entire public that has not studied gemology and is liable to mistakenly think there is a standard. There isn't – at least not at the moment.

 

Disclaimer

     Let's have a look at the disclaimer that accompanies the gemological certificates of one of the world's better-known institutes, and appears in the same or similar form on the certificates issued by all the other leading laboratories. "This report does not constitute a guarantee, estimate or evaluation … the laboratory is not responsible for and does not guarantee anything related to this report."

    Were you aware of this? It seems no one gives much thought to this disclaimer, even though it appears on the gemological certificates – and justifiably so, for in the absence of a universal standard for gemological grading, it's impossible to provide an objective evaluation or guarantee that another examination will yield identical results.

 

Color Grading

    Take, for instance, a stone that is at the upper border of H, but is still within the H grade. Will every gemological laboratory grade the stone as an H, or can we assume that some will grade it as a G? To take the point even further we ask, will ten graders in the same laboratory grade this stone as an H or will some of them, even in the same laboratory, observing the stone under the same conditions, grade it as a G?

    The human eye is limited. Most people have difficulty differentiating between two or even three color grades.  Most graders examine stones from the two master sides, as there are differences between the way the left and right eyes see things. Men see different colors than women do, both see colors differently in the morning and the afternoon and the impression also varies between New York and New Zealand or Newcastle.

     To continue on the matter of color grading: on page 131 of the GIA Diamond Grading Manual, there is a paragraph about examining the color of the stone face down and another one about examining it face up. A third paragraph, which sums up those two, tells us to "estimate the color grade based on a combination of the impressions in both positions." This clearly indicates that grading is a subjective, not objective matter. Moreover, there is no explanation in this paragraph of the relative weight to be given the color grading based on viewing the stone face up (which is customary in gemological laboratories) compared with the color seen when the stone is face down (the way the person wearing a piece of jewelry and those looking at him or her see the stone). To eliminate any doubt, let me say that in presenting these quotations and examples from the GIA, I am not arguing for or against the grading method used by this respected and important laboratory. I use these examples to highlight the point that even this laboratory, the uncontested world leader in its field, holds that there  is no standardization of diamond grading.

 

Clarity Grading

   We have extensively discussed the subject of color grading. The situation is no different in the field of clarity grading. The number of flaws in a stone is a fairly objective matter. It can be assumed that a gemologist in Hong Kong, Israel or Antwerp will record the same result in this respect. However, when examining the size and location of a flaw, one gemologist may think it is as large as an elephant, while another will see it as a tiny mouse. To one it may seem the location is absolutely disastrous, while another will consider it totally ordinary and no cause for concern. Therefore, different gemologists in the same laboratory will give a different grade of clarity to the same stone. That is the unwritten reason that two gemologists check every stone, with a third being called upon in cases of controversy between them. The grading, then, is the outcome of a majority vote. Standards are not set by majority votes.

 

Cut Grading

    A new grade has recently been introduced – the cut grade. Although cut is sometimes a synonym for processing, I can assure you than any dealer in Israel, India, the US, Belgium, Hong Kong or any other country will tell you that "cut" means "shape" – as in the original, widely accepted (and here "universal" is the right word) definition of the 4 Cs (carat, color, cut and clarity).

      In grading cut as interpreted today, there are two problems: first – we only know how to grade the cut of round stones, which represent about 50 percent of all diamonds sold in the market today. In the grading of rounds we only know what an optimal stone is, and from this very limited definition we develop "tolerances" – flexible borders – that expand the definition to include an increasing number of stones in the high end of the grade scale. All graders are intelligent, anyone can be right and no one can say they have received the word from on high that things should be done their way alone.

 

Different Grading Systems

   Table 1 shows four leading systems for grading clarity. Some are similar and some are different from one another. Table 2 shows four leading systems for grading color. Here we find no similarity among the different laboratories. The preference of a given system by a certain laboratory or country does not make it more correct, and certainly not a standard.

Table 1: The Four Leading Systems for Grading Clarity

GIA

Russia

CIBJO

SCAN DN

FL

FL

IF

1

IF

IF

VVS1

2-3

VVS1

VVS1

VVS2

3

VVS2

VVS2

VS1

4

VS

VS1

VS2

5-6

VS2

SI1

7

SI

SI1

SI2

7a

SI2

I1

8

P1

1st pique

I2

9

P2

2nd pique

I3

10

P3

3rd pique

Table 2: The Four Leading Systems for Grading Color

GIA

Russia

CIBJO

SCAN DN

D

1

Exceptional + White

River

E

2

Exceptional White

 

F

3

+Rare White

 

G

4

Rare White

Top Wesselton

H

5

White

Wesselton

I

6

Slightly Tinted White

Top Crystal

J

7

 

Crystal

K

8

Tinted White

 

L

8-1

 

Top Cape

M

8-2

Tinted Color 1

 

N

8-3

 

Cape

O

 

Tinted Color 2

 

P

8-4

 

Light Yellow

Q

 

Tinted Color 3

 

R

 

 

 

S

 

Tinted Color 4

 

T

8-5

 

 

U-Z

 

 

Yellow

 

A System, Not a Standard

     I believe that these two examples clarify the fact that at present we can talk about a system – or to be more accurate, systems – but there is no such thing as a standard. As the GIA says (again I quote the GIA – there is no question about it; this is the laboratory that sets the tone): "Since its introduction in the early 1950s, GIA's D-Z scale has been used to color grade the overwhelming majority of colorless to light yellow gem-quality polished diamonds" (John M. King, Ron H. Geurts, Al M. Gilberston and James E. Shigley, Gems & Gemology, Winter 2008). Anyone can see, then, that the leaders of the GIA are cautious and use the word "scale," and not "standard." Furthermore, they also say that this is the leading system, and not the exclusive or only one.

 

A Standard Mark

     Recently there has been some confusion, with some believing that if a laboratory has ISO 17025 it complies with a standard. However, the ISO international standard indicates quality of laboratory management, and not diamond grading. ISO 17025 was written for metrology laboratories, which require a higher management standard than ISO 9001, which is the accepted standard for quality management of gemological laboratories. It is good to require that the management of gemological laboratories complies with the 17025 standard, but such compliance does not signify that they are any better or worse as gemologists, and does not make their grading standard.

 

In Summary

    As long as the technique is subjective and not objective, we cannot use the word "standard" in reference to diamond grading, because the term is misleading. To date the beauty in our industry is the variance in grading, which keeps the trade within the realm of illusion rather than commodities. I advocate a true standard, but its use must be genuine and well founded. It will be a welcome day when we start trading diamonds as a commodity, because it will take the diamond trade to new heights. We aren't there yet.

 

The author is the owner and director of EGL Asia.

 
 
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