Colored Diamonds
From the D-to-Z scale to fancy diamonds: yellow, brown, blue, green, pink and red, and what causes each color.
GIA describes a colored diamond by its hue, its tone (how light or dark) and its saturation, choosing among 27 hues, with terms such as Fancy Light, Fancy Intense or Fancy Vivid. The colors here are our own approximations of natural-color diamonds, not laboratory standards.
Colorless diamond, D to Z
GIA, 1953
In 1953 GIA introduced its D-to-Z scale for diamonds with almost no color. It sorts them into five groups: colorless (D–F), near-colorless (G–J), faint (K–M), very light (N–R) and light (S–Z). Past that, a diamond with enough color is graded as a fancy color.
GIA starts at D to avoid confusion with older systems. Stones are graded face down, under controlled light, against master stones.
Grades D–F
The colorless group, the rarest.
Material: Diamond graded D–F
RGB(248, 250, 252)
Grades G–J
Near-colorless: the color is often unnoticeable except by trained graders.
Material: Diamond graded G–J
RGB(247, 245, 236)
Grades K–M
Faint: the color is still hard to see for an untrained eye.
Material: Diamond graded K–M
RGB(244, 238, 215)
Grades N–R
Very light: a subtle color shows in larger stones.
Material: Diamond graded N–R
RGB(241, 230, 193)
Grades S–Z
Light: the color shows in stones of any size, slightly yellow or brown.
Material: Diamond graded S–Z
RGB(236, 220, 166)
Yellow diamond
Colored by nitrogen
According to GIA, about 74 % of the fancy yellow diamonds it receives owe their color to «cape» features, above all the N3 defect: three nitrogen atoms beside a vacancy.
The same defects give many D-to-Z diamonds their yellowish tint, but in such low amounts that they never reach a fancy grade.
Yellow diamond · hue
The main hue, the color the gem is named by.
Material: Yellow diamond, faceted, hue
RGB(243, 207, 58)
Yellow diamond · light
The light part, where the stone is thinnest or light passes straight through.
Material: Yellow diamond, faceted, light
RGB(248, 226, 124)
Yellow diamond · deep
The deepest part, in the facets in shadow.
Material: Yellow diamond, faceted, deep
RGB(201, 160, 19)
Yellow diamond · sparkle
The sparkle, where light bounces off the facets back to the eye.
Material: Yellow diamond, faceted, sparkle
RGB(255, 241, 176)
Brown diamond
Colored by plastic deformation
Its color comes from clusters of vacancies in the crystal lattice, created by the natural plastic deformation of the diamond.
Among D-to-Z diamonds, about 5 % show a brown tint instead of a yellow one.
Brown diamond · hue
The main hue, the color the gem is named by.
Material: Brown diamond, faceted, hue
RGB(138, 90, 53)
Brown diamond · light
The light part, where the stone is thinnest or light passes straight through.
Material: Brown diamond, faceted, light
RGB(184, 135, 94)
Brown diamond · deep
The deepest part, in the facets in shadow.
Material: Brown diamond, faceted, deep
RGB(90, 54, 24)
Brown diamond · sparkle
The sparkle, where light bounces off the facets back to the eye.
Material: Brown diamond, faceted, sparkle
RGB(217, 180, 143)
Blue diamond
Boron, radiation or hydrogen
Blue is often linked to boron: more boron generally means a stronger blue. But it also comes from defects made by radiation or involving hydrogen, which give grays and violets too.
Boron does not make a diamond blue if enough competing defects are present.
Blue diamond · hue
The main hue, the color the gem is named by.
Material: Blue diamond, faceted, hue
RGB(79, 127, 184)
Blue diamond · light
The light part, where the stone is thinnest or light passes straight through.
Material: Blue diamond, faceted, light
RGB(134, 169, 214)
Blue diamond · deep
The deepest part, in the facets in shadow.
Material: Blue diamond, faceted, deep
RGB(43, 79, 128)
Blue diamond · sparkle
The sparkle, where light bounces off the facets back to the eye.
Material: Blue diamond, faceted, sparkle
RGB(184, 208, 236)
Green diamond
Radiation, H3, hydrogen or nickel
GIA identifies four causes: GR1 defects, empty lattice sites left by natural radiation; the green luminescence of H3 centers; and defects related to hydrogen and to nickel.
H3 makes green in a curious way: it does not absorb light, it emits it.
Green diamond · hue
The main hue, the color the gem is named by.
Material: Green diamond, faceted, hue
RGB(111, 174, 106)
Green diamond · light
The light part, where the stone is thinnest or light passes straight through.
Material: Green diamond, faceted, light
RGB(163, 208, 155)
Green diamond · deep
The deepest part, in the facets in shadow.
Material: Green diamond, faceted, deep
RGB(63, 122, 61)
Green diamond · sparkle
The sparkle, where light bounces off the facets back to the eye.
Material: Green diamond, faceted, sparkle
RGB(205, 232, 198)
Pink diamond
The 550 nm band
The most common cause of pink is a broad absorption band centered around 550 nanometers, whose defect has not yet been identified.
The color often sits in lamellae caused by natural plastic deformation, which only form after a long stay at over 900 °C.
Pink diamond · hue
The main hue, the color the gem is named by.
Material: Pink diamond, faceted, hue
RGB(231, 154, 180)
Pink diamond · light
The light part, where the stone is thinnest or light passes straight through.
Material: Pink diamond, faceted, light
RGB(243, 194, 210)
Pink diamond · deep
The deepest part, in the facets in shadow.
Material: Pink diamond, faceted, deep
RGB(194, 106, 138)
Pink diamond · sparkle
The sparkle, where light bounces off the facets back to the eye.
Material: Pink diamond, faceted, sparkle
RGB(250, 221, 231)
Red diamond
The pink family
GIA studies red diamonds together with pinks and purples, a family in which the most common cause of color is the 550 nm absorption band.
In this family the color is often spread in thin lamellae; cutters orient them so the stone looks evenly colored face up.
Red diamond · hue
The main hue, the color the gem is named by.
Material: Red diamond, faceted, hue
RGB(163, 18, 44)
Red diamond · light
The light part, where the stone is thinnest or light passes straight through.
Material: Red diamond, faceted, light
RGB(201, 56, 79)
Red diamond · deep
The deepest part, in the facets in shadow.
Material: Red diamond, faceted, deep
RGB(107, 10, 27)
Red diamond · sparkle
The sparkle, where light bounces off the facets back to the eye.
Material: Red diamond, faceted, sparkle
RGB(224, 106, 126)
Pigmentoria is an independent color atlas. Gem, variety, place and trade names (for example «pigeon's blood» or «Paraíba») are used descriptively only and do not indicate the origin, quality, treatment or certification of any stone. The colors are our own digital approximations, not official standards of any laboratory. GIA, CIBJO, LMHC, SSEF, Gübelin and the other organisations cited belong to their owners; Pigmentoria is not affiliated with or endorsed by them.