Types of Clarity in Gemstones
1. Transparency Types
These terms describe how much light passes through a gem.
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Transparent: Light passes through the stone clearly and undistorted, allowing objects to be seen clearly through it. Examples: Fine diamond, sapphire, and emerald.
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Semi-Transparent: Light passes through the stone, but it is diffused. Objects on the other side are seen as blurred shapes. Examples: Some sapphires, garnets, and topaz.
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Opaque: No light passes through the stone. It is impenetrable to light. Examples: Lapis lazuli, turquoise, and malachite.
2. Common Clarity Grades (Based on the GIA Diamond Scale)
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Included (I1, I2, I3): Obvious inclusions that are visible to the naked eye. They can affect transparency, durability, and brilliance.
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Slightly Included (SI1, SI2): Inclusions are noticeable with medium effort using a 10x loupe and may be visible to the naked eye. SI1 inclusions are often harder to see without a loupe than SI2.
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Very Slightly Included (VS1, VS2): Minor inclusions that are difficult to see with a 10x loupe. They are not visible to the naked eye. This is considered excellent clarity.
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Very, Very Slightly Included (VVS1, VVS2): Minute inclusions that are extremely difficult to see under 10x magnification. They are invisible to the naked eye. This is a high grade of clarity.
3. Descriptive Clarity Terms
These terms describe how a stone appears to the viewer, not under magnification.
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Eye Clean: A practical term meaning that no inclusions are visible to the naked eye (without magnification). A stone can be graded SI or VS and still be "eye clean," which is often an excellent value.
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Loupe Clean: A term meaning no inclusions are visible under 10x magnification. This is very rare and indicates a stone of exceptional clarity. It is similar to a Flawless or Internally Flawless grade.