Diamonds


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 luster …

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