Black Diamonds
| Property | Details |
|---|
| Cause of Color | Dense inclusions of graphite, pyrite, or hematite that make the stone opaque |
| Types | Natural Fancy Black (included), Carbonado (polycrystalline), Treated (irradiated/heated) |
| Rarity | Natural black diamonds are uncommon; treated black diamonds are widely available |
| GIA Grading | Graded only as “Fancy Black” (no intensity scale — it is either black or it isn't) |
| Famous Examples | Black Orlov (67.50 ct), Spirit of de Grisogono (312.24 ct), Korloff Noir (88 ct) |
| Mohs Hardness | 10 (same as all diamond), but may be more fragile due to heavy inclusions |
| Price Range (1ct) | $1,500 – $5,000 (natural); $300 – $1,500 (treated) |
Overview
Black diamonds have surged in popularity over the past two decades, particularly in men's jewelry, fashion rings, and modern engagement rings. Unlike other colored diamonds that get their color from trace elements or lattice distortion, black diamonds are colored by such dense concentrations of dark inclusions — typically graphite, pyrite, or hematite — that the stone becomes completely opaque.
Black diamonds do not sparkle in the same way as transparent diamonds. Instead, they display a metallic, adamantine luster on their surface that many find dramatic and striking. This unique aesthetic has made them a favorite for contemporary jewelry design.
Types of Black Diamonds
Natural Fancy Black: These are natural diamonds so heavily included with dark minerals that they appear uniformly black. They are mined alongside other diamonds and graded by GIA as “Fancy Black.” They are opaque and do not display the fire or brilliance of transparent diamonds.
Carbonado: A mysterious type of polycrystalline diamond found only in Brazil and the Central African Republic. Carbonado is not a single crystal but a mass of tiny diamond crystals fused together. Some scientists theorize that carbonados may have an extraterrestrial origin, formed in supernovae and delivered to earth via asteroid impact. Carbonados are extremely tough but rarely used in fine jewelry.
Treated Black: The most common and affordable type. White or heavily included diamonds are subjected to high-heat treatment or irradiation to turn them uniformly black. These are the black diamonds you'll find in most commercial jewelry. They must be disclosed as treated.
GIA Grading
Black diamonds are unique in the GIA grading system. Because they are opaque, the standard colored diamond grading scales for tone and saturation do not apply. GIA issues a “Colored Diamond Identification and Origin Report” rather than a full grading report, and the color is described simply as “Fancy Black.” There is no “Fancy Vivid Black” or “Fancy Light Black.”
Durability Considerations
While black diamonds have the same Mohs hardness of 10 as any diamond, the heavy inclusions that give them their color can also create internal weaknesses. Some black diamonds are more prone to chipping or fracturing along inclusion planes than transparent diamonds. This makes protective settings (bezel, channel) a wise choice for rings, especially for everyday wear.
Natural vs Treated
Natural: Rarer and more expensive ($1,500–$5,000+ per carat). Look for GIA identification confirming “natural” origin. Natural blacks may show slight translucency at thin edges.
Treated: Widely available and affordable ($300–$1,500 per carat). Produced by heating or irradiating heavily included or fracture-filled diamonds. Appear uniformly opaque black. An excellent value for jewelry use.
Buying Tips
- Decide between natural and treated based on your budget and priorities.
- Choose protective settings (bezel or channel) for everyday rings.
- Black diamonds pair dramatically with white gold, platinum, and rose gold.
- They look striking in contrast designs with white diamonds (halos, pavé bands).
- Popular for: men's wedding bands, fashion rings, stud earrings, pendant necklaces.
- Check for obvious surface-reaching fractures, which can affect durability.
Explore more colors in our Colored Diamond Guide.