Diamond Properties Chart
Quick facts about the optical and physical properties of diamonds.
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Source | Hardhigh | Hardlow | SGhigh | SGLow | RIHigh | RILow | Birefringence | Optics | Disper-sion |
Natural & Synthetics | 10 | 10 | 3.53 | 3.51 | 2.417 | 2.417 | – | I | .044 |
Formula: C
Crystallography: Cubic
Colors: Colorless, gray, yellowish brown, brown, yellow, blue, pink, orange red purple green black
Transparency: Transparent to Opaque
Pleochroism: None
UV long: Inert to strong, most colors, blue phosphorescence possible. Black inert. Yellow to greenish yellow phosphorescence in synthetics.
UV short: Inert to strong, most colors, blue phosphorescence possible. Black inert. Yellow to greenish yellow phosphorescence in synthetics.
Absorption Spectrum:Cape series, 415.5nm, other lines possible. Brown and green, 504nm and often 415.5nm, other lines possible. Yellow, 504nm. Pink, only a vague band centered on 563nm. Irridated yellow, 415.5nm, 497nm, 504nm and 597nm.
Polish Luster: adamantine
Fracture: step like
Fracture Luster: adamantine
Cleavage: perfect
Phenomena: none
Toughness: Very good
Size: To large
Rarity: Colorless, very common. Brown, somewhat common, other colors rare.
Heat Sensitive: No
Enhancements: Irradation, detect by spectrum. Coating, laser drilling, fracture filling. Detect with magnification.
Identifying Characteristics:
Natural Diamonds: Adamantine luster, sharp facet edges, bearded girdles, naturals on girdle, crystal inclusions, trigons, no see through effect.
CVD Diamonds: line at 737nm.
HPHT Diamonds: hour glass of graining, inclusions with metallic…
International Gem Society
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