Clarity Grading Diamonds


Step 4: Gem Grading

Lesson 12

The Rise of the Four Cs Grading System

Until the mid 20th century, purchasing a diamond was very confusing. The grading terms dealers used, like “AA” and “AAA,” meant nothing to the average consumer. To make matters worse, even the definitions of these terms varied from dealer to dealer. Expert merchants fared little better. For example, they could wait months for an order of “AAA” clarity graded diamonds. On arrival, they might find the gems to be “AA” grade at best. They could either accept the order and offer lower grade gems to their customers or return the stones. Of course, this would mean more months of waiting and possible disputes. These conditions benefited no one.

To address this situation, various grading systems were introduced. However, each new system came with a new set of terms and definitions. Thus, they simply produced more confusion.

In 1953, the Gemological Institute of America (GIA) successfully introduced the now virtually universal diamond grading system. Their system is based on the Four Cs: carat, color, cut, and clarity. These standards now made it possible for dealers to have a good idea of a …

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Full Article Details


Content Length 4647 words
Reading time 23 min 14 sec

Here's what you get if you unlock this article:

  • The Rise of the Four Cs Grading System
  • Criteria for Clarity Grading Diamonds
  • Blemishes
    • Polishing Marks
    • Nicks and Chips
    • Scratches and Abrasions
    • Percussion Marks or Bruises
    • Cavities
    • Knots
    • Twinning, Knot, or Grain Lines
    • Crystal Growth Lines
    • Facets Cut Parallel with the Grain
    • Burn Marks
    • Naturals
    • Rough Girdle
    • Extra Facets
  • Inclusions
    • Included Crystals
    • Carbon Spots
    • Pinpoint Inclusions
    • Clouds
    • Bearding
    • Cleavage
    • Fractures
    • Feathers and Hairline Feathers
  • Treatments and Clarity Grading Diamonds
    • Clarity Enhancement
    • Laser Drilling
  • What Do Clarity Grades Mean?
  • Diamond Clarity Grades Defined
    • F: Flawless
    • IF: Internally Flawless
    • VVS1: (Very, Very Small Inclusions 1)
    • VVS2: (Very, Very Small Inclusions 2)
    • VS1: (Very Small Inclusions 1)
    • VS2: (Very Small Inclusions 2)
    • SI1: (Small Inclusions 1)
    • SI2: (Small Inclusions 2)
    • SI3: (Small Inclusions 3)
    • I1: (Included 1)
    • I2: (Included 2)
    • I3: (Included 3)
  • Clarity Grading Diamonds: Examples
    • VVS Inclusions
    • VS Inclusions
    • SI Inclusions
    • I Inclusions
    • Reflected Inclusions
    • Structural Weaknesses
  • More Examples of Clarity Grading Diamonds
  • Plotting Blemishes and Inclusions on Your Diamond Grade Report
    • Plotting Blemishes
    • Plotting Inclusions
    • Plotting Examples

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