Chapter 10 Flashcards
What was lacking in the diamond business before the 1950s?
A way to accurately describe a diamond’s features
Grading systems existed but were not precise, leading to varied interpretations of diamond quality.
What system was introduced in 1953 to standardize diamond grading?
The GIA Diamond Grading System
This system eliminated confusion in diamond evaluation and communication of quality.
How many grades are in the GIA clarity grading scale?
11 grades
The grades range from Flawless (FL) to Included (I1, I2, I3).
What are the two categories of Very Very Slightly Included in the GIA grading scale?
VVS1 and VVS2
These grades indicate very minimal inclusions that are difficult to detect.
What are the two categories of Very Slightly Included in the GIA grading scale?
VS1 and VS2
These grades indicate slight inclusions that are difficult to detect without magnification.
What are the two categories of Slightly Included in the GIA grading scale?
SI1 and SI2
These grades indicate inclusions that may be visible to the naked eye.
What are the three levels of Included in the GIA grading scale?
I1, I2, and I3
These grades indicate inclusions that are easily visible and affect the diamond’s appearance.
Why is understanding clarity grades valuable for those who buy and sell diamonds?
It helps confirm the accuracy of a diamond’s stated clarity grade
This skill aids in effective communication with clients and customers.
What does the clarity scale impact in terms of diamonds?
A diamond’s clarity grade and its value
Different combinations of inclusions and blemishes can significantly affect clarity.
True or False: The GIA Diamond Grading System is only recognized in the U.S.
False
The system has become the internationally accepted standard for grading diamonds.
Fill in the blank: The GIA clarity grading scale includes Flawless (FL), Internally Flawless (IF), and three levels of _______.
Included
Included grades are I1, I2, and I3.
What factors influence the clarity grade of a diamond?
Size and visibility of inclusions
Larger and more visible inclusions generally lower the clarity grade.
How does the size of an inclusion relate to the diamond’s clarity?
The size of the inclusion is considered in relation to the size of the diamond
Larger inclusions typically have a greater impact on the clarity grade.
What usually establishes the clarity grade in a diamond with inclusions of different sizes?
One or two of the larger inclusions
Smaller inclusions seldom affect the clarity grade.
True or False: Smaller inclusions always affect the clarity grade of a diamond.
False
Smaller inclusions usually do not affect the clarity grade significantly.
What effect do inclusions have on clarity grade?
The more inclusions seen face-up at 10x, the greater the effect on clarity grade.
Inclusions act like mirrors, reflecting multiple times and making them more apparent.
How are clarity grades determined?
Grades are based on how readily inclusions can be seen rather than by counting them.
A diamond with many minute pinpoints can still qualify as VVS.
What is the effect of the location of inclusions on clarity grading?
Inclusions are more visible when directly under the table; those under the crown facets or near the girdle are harder to see.
Examining the stone from several angles helps find all characteristics.
What impact does a central location have on an inclusion’s effect on clarity?
A central location increases an inclusion’s impact on the clarity grade.
Crystals directly under the table affect the grade more than feathers under the star facet.
What is relief in terms of inclusions?
Relief is the contrast between an inclusion and its host gem.
High relief means more apparent inclusions, while low relief means less apparent.
How does the color of inclusions affect their visibility?
Colored inclusions (black, brown, dark red, green) are easier to see and may lower the grade more than colorless inclusions.
Most diamond inclusions are white or colorless.
What does ‘nature’ refer to in the context of diamond inclusions?
Nature refers to the type of characteristic and its effect on the diamond.
Inclusions impact clarity more than blemishes.
How does internal graining compare to a physical break in terms of clarity impact?
Internal graining has less impact on clarity than a physical break of similar size and appearance.
A minute feather has less impact than an included crystal of similar size.
What concerns are associated with deep feathers in diamonds?
Deep feathers that extend from crown to pavilion or penetrate significantly can pose durability risks and lower the grade.
Durability issues rarely affect clarity due to the cutting process.
What are inclusions and blemishes in diamonds used for?
To determine its clarity grade
Inclusions are internal flaws, while blemishes are external flaws.
What does a diamond grader analyze to reach a clarity grade?
Characteristics of inclusions and blemishes
The analysis aims to accurately represent the diamond’s quality.
What is essential for developing skills in diamond grading?
Practice
Training your eye enhances confidence and skill in the diamond industry.
What is required for accurate and consistent grading results?
A systematic grading method
This method ensures all characteristics that might affect clarity are located.
What could happen if a precise method is not used to examine a diamond?
You might miss small flaws
Mistakes in grading can lead to costly errors.
What does the wedge technique involve in clarity grading?
Dividing the stone into eight sections
This allows for a systematic search for clarity characteristics.
From the pavilion view, what does each wedge include?
A pavilion main facet, two lower half facets, and one-eighth of the girdle
This structure helps in thorough examination.
From the crown view, what does each wedge include?
Two upper half facets, a bezel facet, half of two star facets, and one-eighth of the table
This assists in identifying clarity characteristics.
What is the first step in numbering the wedges in a diamond?
Find a marker characteristic and use it as a starting point for counting the wedges.
Why is it important to choose a characteristic closer to the girdle for counting wedges?
It is unique and easy to identify.
What should you note the first identified area as?
Wedge 1.
How does the first impression influence clarity grading?
It is very important and influences how you proceed with the examination.
What does a higher clarity diamond require during examination?
A more careful examination.
Is a microscope necessary for clarity grading?
No, but it is commonly used to locate and identify characteristics.
What is the benefit of using increased magnification during examination?
To properly identify and document a characteristic.
What should you do if a trained grader can’t see a clarity characteristic at 10x?
It doesn’t affect the clarity grade.
What is the first action to take when examining a diamond?
Clean the diamond thoroughly with your gem cloth.
How should the diamond be held for the initial clarity examination?
Girdle-to-girdle in tweezers.
What magnification should be used for the initial impression of clarity?
10x magnification.
What type of illumination is recommended for the initial clarity examination?
Darkfield illumination.
What position should the diamond be in for the second examination step?
Table-to-culet with the pavilion in an upright position.
What should you do after rotating the diamond once?
Familiarize yourself with the types of characteristics present.
How should a round brilliant diamond be divided for examination?
Into eight wedge-shaped sections.
What is the first step in examining a diamond?
Select a marker characteristic to designate the first section or wedge.
What should you examine first when inspecting the first wedge of a diamond?
The pavilion surface.
What is the order of examination for a diamond?
Pavilion surface, girdle area, face-up view, crown surface, diamond’s interior.
What is the recommended way to examine the girdle area of a diamond?
Slowly turn the diamond.
How should the diamond be held for examining the table and culet areas?
Face-up and girdle-to-girdle in tweezers.
What tool is used to examine a diamond’s clarity characteristics?
A 10x loupe.
When grading diamonds, what must the grader analyze?
The diamond’s inclusions and blemishes.
What does a clarity grade represent?
The quality of the diamond.
How should the diamond be turned during examination?
In a consistent direction, for example, always to the right.
What is essential for developing skills in diamond examination?
Practice.
True or False: Experience looking at diamonds is important for gaining confidence and skill.
True.
Fill in the blank: After completing your examination, you will assign a clarity grade based on the type of characteristics present and their overall appearance in a _______.
[10x loupe]
What should you check for in lower-clarity diamonds?
Eye-visible inclusions with your unaided eye.
What is a callable characteristic?
A callable characteristic is one that affects clarity and is visible at 10x magnification.
Callable characteristics impact the overall clarity grade of a diamond.
What is a non-callable characteristic?
A non-callable characteristic does not affect clarity and can exist on a Flawless diamond.
These characteristics can include inclusions and blemishes visible only at magnification higher than 10x.
At what magnification are callable characteristics visible?
Callable characteristics are visible at 10x magnification.
This magnification is standard for assessing diamond clarity.
Give examples of non-callable characteristics.
Examples of non-callable characteristics include:
* Inclusions visible only at +10x
* Blemishes visible only at +10x
* Internal graining
* Extra facets
* Naturals
These characteristics may be visible at 10x but do not impact clarity.
What might be considered non-callable even when visible at 10x?
Internal graining, extra facets, and naturals might be considered non-callable.
Their classification depends on appearance or viewing position.
What is the challenge in defining clarity grades for diamonds?
The clarity characteristics in diamonds come in an endless variety of combinations
Which clarity grade can be precisely defined?
Flawless
What do the descriptions of VVS through I grades focus on?
Typical inclusions, not blemishes
Why are blemishes rarely considered in grades lower than IF?
Blemishes rarely have much effect on grades lower than IF
What do clarity grades primarily describe?
Typical grade-setting characteristics: inclusions or blemishes
Does the presence of additional characteristics affect the clarity grade?
No, other characteristics might be present but don’t affect the grade
What might an I-graded diamond have in common with a VVS-graded diamond?
Both might have pinpoints
What typically determines the clarity grade of a diamond?
The largest or most visible characteristics
Fill in the blank: The GIA clarity grading scale includes _____ grades.
11
True or False: An I-graded diamond’s grade is the sum of all visible characteristics.
False
Who started working on a diamond grading system in 1952?
Richard T. Liddicoat
He was the president of GIA at that time.
What are the three main segments of the diamond grading system proposed by GIA?
- Color
- Clarity
- Make
‘Make’ describes the relative quality of a finished diamond’s proportions and finish.
What was the issue with existing clarity grading systems before GIA’s development?
No single system that everybody used and understood
Terms like Flawless, VVS, VS, SI, and I had broad definitions.
How many grades were included in the initial diamond grading system unveiled by Liddicoat in 1953?
Nine grades
The grades were Flawless, VVS1, VVS2, VS1, VS2, SI1, SI2, I1, and I2.
What does the ‘I’ in the initial grading system stand for?
Imperfect
When and where was the first diamond grading class taught?
April 1953 in New York
The class drew 11 students from neighboring states.
What significant changes to the clarity grading system occurred in the 1970s?
- Addition of the IF grade
- Addition of the I3 grade
The IF grade was added to prevent excessive alteration of stones for the Flawless grade, and the I3 grade accounted for stones with large, obvious inclusions.
What was the reason for adding the IF grade to the clarity grading system?
Too many stones were being butchered by removing surface blemishes
This often ruined proportions and symmetry.
What was the Imperfect grade renamed to in the 1990s?
Included
What is the clarity grade based on?
The overall appearance of the diamond in a fully corrected 10x loupe.
Which diamond shape is most closely described in the clarity descriptions?
Round brilliants in typical jewelry sizes.
What factor can make inclusions easier to see in diamonds?
Larger stones and some fancy shapes.
What do some industry professionals use to describe the overall clarity of a diamond?
Variations on the terms ‘purity’ or ‘quality’.
What does a gem with good purity or high quality indicate?
It has few clarity characteristics.
What is the clarity grade for a diamond that shows no inclusions and no blemishes under 10x magnification?
Flawless (FL).
What can a Flawless diamond have that does not disqualify it from being labeled as such?
Features like extra facets, naturals confined to the girdle, internal graining, inscriptions, and mounting features.
Fill in the blank: A Flawless diamond shows no _______ and no blemishes when examined under 10x magnification.
inclusions
True or False: A Flawless diamond can have internal graining that affects its transparency.
False.
What type of graining is acceptable in a Flawless diamond?
Internal graining that’s not reflective, white, or colored, and doesn’t significantly affect transparency.
What is a requirement for naturals to not disqualify a diamond from being Flawless?
They must be entirely confined to the girdle and not thicken or distort it.
What kind of inscriptions are acceptable in a Flawless diamond?
Inscriptions that aren’t internal and don’t penetrate the surface.
What does an Internally Flawless (IF) diamond show under 10x magnification?
Only insignificant blemishes—no inclusions.
When was the Internally Flawless (IF) grade added by GIA?
In the 1970s.
What can normally remove blemishes on an IF diamond?
Very minor repolishing.
What is an exception to the removability of blemishes on an IF diamond?
Surface graining.
What does VVS stand for in diamond grading?
Very Very Slightly Included.
How visible are inclusions in a VVS1 diamond under 10x magnification?
Extremely difficult to see.
What might a typical VVS1 stone show under 10x magnification?
A pinpoint or two, or reflective internal graining.
How does the visibility of inclusions differ between VVS1 and VVS2 diamonds?
VVS1 inclusions are extremely difficult to see, while VVS2 inclusions are very difficult to see.
What types of surface-reaching inclusions can affect the grade of VVS diamonds?
Minute feathers, chips, or cavities.
If inclusions are more visible through the crown of a diamond, what grade might it receive?
VVS2.
Fill in the blank: A VVS2 diamond has inclusions that are ______ to see.
very difficult
True or False: An IF diamond has inclusions that can be seen under 10x magnification.
False.
What do VS1 and VS2 stand for in terms of diamond clarity?
Very Slightly Included 1 and Very Slightly Included 2
What type of inclusions are present in VS stones?
Minor inclusions that range from difficult (VS1) to somewhat easy (VS2) to see under 10x magnification
What factors determine the grade of a VS stone?
Overall visibility considering all five clarity factors
What are typical inclusions that might affect the grade of a VS stone?
- Small crystals
- Knots
- Distinct clouds
- Minor surface-reaching inclusions such as feathers, cavities, or indented naturals
Can a VS stone contain an eye-visible inclusion?
Yes, in very rare cases
What must be considered when evaluating an eye-visible inclusion in a VS stone?
- Size
- Nature
- Location
- Number
- Relief of the inclusion in relation to the size and shape of the stone
In the context of VS stones, what is an example of a situation where an eye-visible inclusion might still be acceptable?
An emerald cut that’s more than 1 carat in size can have an eye-visible included crystal under the corner of the table and still be in the VS range
What does SI stand for in diamond clarity grading?
Slightly Included
What are the two subgrades of SI stones?
SI1 and SI2
What is the visibility of inclusions in SI1 stones under 10x magnification?
Easy to see
What is the visibility of inclusions in SI2 stones under 10x magnification?
Very easy to see
What factors influence the grade of SI diamonds?
Overall visibility of inclusions considering all five clarity factors
List typical inclusions that might affect the grade of a diamond.
- Crystals
- Feathers
- Clouds
- Twinning wisps
Can a stone with an eye-visible inclusion be graded SI?
Yes
Are the characteristics in an SI1 diamond usually visible face-up without magnification?
No
Are eye-visible inclusions more common in SI1 or SI2 stones?
SI2 stones
Is SI3 a part of the GIA clarity scale?
No
Is SI3 used in diamond pricing lists?
Yes, by some in the trade
What is the visibility of inclusions in diamonds rated as I range?
Inclusions are obvious under 10x magnification.
What are typical characteristics of inclusions in I range diamonds?
They can be seen face-up without magnification, seriously affect the stone’s durability, and are numerous or large enough to affect transparency and brightness.
How visible are inclusions in I1 diamonds?
Inclusions are usually quite visible to the unaided eye.
How visible are inclusions in I2 diamonds?
Inclusions are easily visible.
How visible are inclusions in I3 diamonds?
Inclusions are extremely easy to see and might affect the stone’s durability.
What is often done with rough diamonds at I3 clarity level?
They are used for industrial purposes and are faceted only if the current market demands it.
Fill in the blank: Inclusions in I1 diamonds are usually _______.
quite visible to the unaided eye.
True or False: Inclusions in I2 diamonds can be seen without magnification.
True
What are clarity characteristics in diamonds?
Features that can act as identifying traits for diamonds
Clarity characteristics include inclusions, blemishes, and transparency.
Why is experience important in assessing diamond clarity?
It helps in accurately grading clarity based on various characteristics
Experience allows for better recognition of subtle differences in clarity.
Fill in the blank: Each diamond has its own combination of _______ characteristics.
clarity
True or False: All diamonds have the same clarity characteristics.
False
What is a clarity grade?
A classification that reflects the clarity characteristics of a diamond
Clarity grades range from Flawless to Included.
What do clarity grades indicate in diamonds?
A range of visibility of inclusions and blemishes
What are flawless stones characterized by?
Essentially free of inclusions and blemishes
What does IF stand for in diamond clarity grading?
Internally Flawless stones have only blemishes
At what clarity grade do inclusions begin to become more visible?
VVS (Very Very Slightly Included)
What is the significance of the lowest clarity grades?
Inclusions are probably the most apparent features of the stone
What challenges do beginning graders face?
Deciding how much importance to place on the characteristics of a diamond
Name one question that helps determine the importance of characteristics in a diamond.
How big are the characteristics?
List all five factors graders look at to determine a clarity grade.
- Size
- Number
- Location
- Relief
- Nature
How does the location of an inclusion affect its visibility?
A large included crystal close to the girdle is less noticeable
Fill in the blank: Flawless stones are essentially free of _______.
[inclusions and blemishes]
True or False: VVS stones have no visible inclusions.
False
What grade is assigned if there are no blemishes or inclusions?
Flawless
What grade is assigned if there are only blemishes?
IF
If inclusions are extremely difficult or very difficult to see, what grade do they fall into?
VVS range
What grade is assigned if inclusions are difficult to somewhat easy to see?
VS range
If inclusions are easy to very easy to see, what grade do they receive?
SI range
What grade is assigned if inclusions are all very easy to see?
I range
What factors affect the clarity grade of a diamond?
Size and shape of the diamond
If two inclusions are of equal size in diamonds of different carat weights, how does it affect their clarity grades?
They will have different impacts on the clarity grade
What characteristic of some fancy shapes makes it easier to see inclusions?
Large tables
Do fancy black diamonds receive clarity grades?
No, fancy black diamonds do not receive clarity grades.
What grading scale might apply to fancy white diamonds?
The GIA Clarity Grading Scale might apply to fancy white diamonds.
Under what condition does a diamond receive a clarity grade?
If the pavilion facets are visible in the face-up position at 10x.
What is a plot in the context of diamonds?
A plot is a map of a diamond’s clarity characteristics.
What do diamond graders use to create plots?
Graders create plots by drawing clarity symbols on crown and pavilion facet diagrams.
What does green ink indicate on a clarity plot?
Blemishes, with the exception of extra facets.
What does red ink indicate on a clarity plot?
Most inclusions, even those that reach the surface.
What do red and green inks used together indicate?
Cavities, indented naturals, knots, etch channels, and laser drill-holes.
What does black ink indicate on a clarity plot?
Extra facets and, if the stone is mounted, the position of the metalwork.
Where do graders plot most characteristics?
On the crown diagram only.
Where are characteristics visible only from the pavilion view plotted?
On the pavilion diagram.
How are characteristics that break the surface plotted?
In every location where they reach the surface.
Why is it important to know how to read a plot?
To understand the clarity characteristics of a diamond.
What are common sources of diamond plots?
Appraisers, in-store gemologists, diamond dealers, and gemological laboratories.
Are all characteristics plotted on a diamond?
No, some grade-setting characteristics aren’t plotted at all.
What types of characteristics do professionals typically plot?
- Characteristics that identify the stone
- Characteristics that set the grade
- Characteristics important in establishing the diamond’s condition
Where might some characteristics that aren’t plotted be mentioned?
In a report’s comments section.
What is a plot in the context of diamonds?
A map of a diamond’s clarity characteristics.
What do diamond graders use to create plots?
Clarity symbols on crown and pavilion facet diagrams.
What does green ink indicate in diamond plotting?
Blemishes, with the exception of extra facets.
What does red ink indicate in diamond plotting?
Most inclusions, even those that reach the surface.
What do red and green inks used together indicate?
Cavities, indented naturals, knots, etch channels, and laser drill-holes.
What does black ink indicate in diamond plotting?
Extra facets and, if the stone is mounted, the position of the metalwork.
Where do graders typically plot most characteristics?
On the crown diagram only.
Where are characteristics visible only from the pavilion view plotted?
On the pavilion diagram.
How are characteristics that break the surface plotted?
In every location where they reach the surface.
What are common sources of diamond plots?
- Appraisers
- In-store gemologists
- Diamond dealers
- Gemological laboratories
Are all characteristics plotted in diamond grading?
No, some grade-setting characteristics aren’t plotted at all.
What type of characteristics do many diamond professionals plot?
Characteristics that identify the stone, set the grade, or are important for establishing the diamond’s condition.
What is an example of a characteristic that can set the grade but is not plotted?
Internal graining.
What features are often plotted because they are useful as identifying features?
Naturals and extra facets.
What makes some plots easier to read than others?
The number of clarity characteristics present.
What is the best method for orienting the diamond to the plot diagram?
Use the wedge technique.
How should you examine a diamond when matching it to its plot?
Hold the diamond girdle-to-girdle and examine it under 10x magnification.
What should you do with the plot while examining the diamond?
Rotate the plot to match your view of the diamond.
What is the purpose of creating a key to symbols after plotting a diamond?
To list the characteristics and symbols shown on the plot
This key is essential for anyone who reads the plot.
In what order are characteristics listed in the key?
In order of importance:
* Laser drill-holes
* Grade-setting inclusions
* Other inclusions
* Naturals and extra facets
Laser drill-holes are prioritized for clear disclosure.
How is grading diamonds compared to detective work?
Both involve searching for clues and analyzing them to reach a conclusion
In diamond grading, the clues are inclusions and blemishes.
What must you do when reading a plot of a diamond?
Match the illustrated clarity characteristics with the real ones in the diamond
The grading has already been done, but verification is necessary.
What is the GIA International Diamond Grading System™?
A universal way to communicate diamond quality
It provides a standardized method for grading diamonds.
What does the GIA clarity grading system include?
An overview of clarity characteristics, identification methods, and their impact on clarity grade
It details how to assess diamond quality.
What is required to become a consistent and skilled diamond grader?
Practical experience
Experience helps in developing grading skills.
What programs offer practical experience in diamond grading?
GIA Graduate Diamonds program and Diamond Grading Lab Class
These programs provide hands-on experience with diamonds and grading instruments.
Who supports and guides students in developing grading skills?
Trained GIA instructors
They provide necessary guidance during the learning process.
Fill in the blank: Practice is the best way to develop your _______.
diamond grading skills
Regular practice ensures success at every level of the diamond industry.
