Assignment 11 - Grading Color Flashcards
What are the basic elements of color?
Hue, tone, and saturation
How do the basic elements of color affect perception of color?
Hues with low saturation will be perceived greyish or brownish. White and black are very dark or very light tones.
The first impression of an object’s basic color
Hue
The degree of darkness or lightness of a color
Tone
The strength or intensity of a color
Saturation
A set of color-comparison diamonds that defines diamond color grades in the normal (D-to-Z) range
Masterstones
A positition that orients a gemstone’s pavillion toward the viewer.
Face-down (or table-down)
A position that orients a gemstone’s crown toward the viewer.
Face-up (or table-up)
How are descriptive terms different for brown and gray diamond colors?
Brown colors above K are described by the letter + the description:
e.g.
K –> “K Faint Brown”
N –> “N Very Light Brown”
S –> “S Light Brown”
Gray colors above K are described only by the description:
e.g.
K to M –> “Faint Gray”
N to R –> “Very Light Gray”
S to Z –> “Light Gray”
Why should’nt you use trade terms to describe diamond color?
Trade terms are often unclear and can be misleading.
What are are the basic tools for color-grading diamonds?
- A neutral background (e.g. DiamondDock,
- A balanced daylight-equivalent light
- A set of masterstones
The optical illusion that causes the ungraded diamond to appear either lighter or darker than the masterstone, depending on which side it is on.
Master-eye effect
How is color grading the same and different for colored and D-to-Z diamonds.
For colored diamonds (any hue other than yellow, brown or gray), the following scales is used:
- Faint (G to M)
- Very Light (N to R)
- Light (S to Z)
- Fancy Light (< Z, but still light)
- Fancy (Medium Saturation or Medium Tone)
- Fancy Intense (Medium Saturation AND Medium Tone)
- Fancy Dark (Dark Tone but Low Saturation)
- Fancy Vivid (High Saturation, but not too dark)
- Fancy Deep (Dark Tone and High Saturation)
Why are colored diamonds graded face-up?
Because cuts can influence the color and diamonds are typically worn face-up.
The basic face-up color of a colored diamond.
Characteristic Color
