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Diamond · Variety of Diamond

Fancy Yellow Diamond

Fancy yellow to vivid canary yellow

Canary Yellow Yellow
Optical properties

Optical characteristics

Ref. index
2.417
Luster
Adamantine
Pleochroism
None None; cubic crystal system is isotropic.
Fluorescence
Variable; some fancy yellows show blue fluorescence which can actually improve face-up appearance in daylight.
Origins

Source localities

South Africa South Africa: Cullinan / Venetia
Legendary ★ Top Source

Historic and important diamond source; historically significant for large and fancy-color diamonds.

30% est. supply
Botswana Botswana: Jwaneng / Orapa
Premium

One of the most important diamond-producing countries.

25% est. supply
Russia Russia: Ural Mountains / Siberia
Major

Classic source for alexandrite, demantoid, diamond and nephrite.

20% est. supply
Australia Australia: New South Wales / Queensland fields
Significant

Commercial sapphire and opal source; many darker blue to blue-green sapphires.

15% est. supply
Namibia Namibia: Erongo / Green Dragon area
Significant

Known for demantoid, spessartite and collector minerals.

10% est. supply
Treatments

Enhancement & treatment

Color Enhancement HPHT Color Treatment High pressure high temperature treatment can remove brown color or create fancy colors in… Color Enhancement Irradiation, Diamond Irradiation changes diamond color by creating color centers, often followed by annealing. Disclosure is…
Inclusions

Inclusions & features

Crystals Crystal Inclusions Under 10x loupe: solid, well-formed mineral crystals trapped inside the host gem. They may… Clouds Pinpoint Clouds Under 10x loupe: concentrations of extremely tiny bright dots that individually are too small… Fractures Feathers and Fractures Under 10x loupe: irregular internal surfaces that catch light and appear bright, wing-like, or… Crystals Radiation Halos Under 10x loupe or microscope: a dark brown, gray, or discolored spherical zone surrounding…
Identification

Instruments used

10x Loupe Your most-used instrument, start every examination here Thermal Probe Confirms diamond, but always follow up with a moissanite tester UV Lamp, Long Wave and Short Wave Fluorescence exposes treatments, synthetics, and origin DiamondView UV Imaging Deep UV imaging for diamond growth structure, HPHT clues, and lab-grown screening Spectroscope Reads characteristic absorption lines, confirms chromium, iron, copper FTIR Spectrometer Laboratory infrared fingerprinting for polymers, fillers, coatings, and some treatments