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Pyroxene

Diopside

Diopside in green, brown, or black varieties

Black Brown Green
Optical properties

Optical characteristics

Ref. index
1.664 – 1.73
Birefringence
0.024 – 0.031
Luster
Vitreous
Pleochroism
Moderate Variable depending on transparency, orientation, and variety.
Fluorescence
Variable to inert.
Origins

Source localities

Russia Russia: Ural Mountains / Siberia
Legendary ★ Top Source

Classic source for alexandrite, demantoid, diamond and nephrite.

33.3% est. supply
Myanmar Myanmar: Mogok Valley
Premium ★ Top Source

Classic source for ruby, sapphire, spinel and other collector gems.

29.1% est. supply
Pakistan Pakistan: Shigar / Swat / Sapat Valley
Premium ★ Top Source

Important source for aquamarine, topaz, peridot, tourmaline and rare minerals.

24.6% est. supply
Italy Italy: Val Malenco / alpine localities
Notable

Known for demantoid and collector minerals.

13.1% est. supply
Inclusions

Inclusions & features

Crystals Crystal Inclusions Under 10x loupe: solid, well-formed mineral crystals trapped inside the host gem. They may… Fractures Feathers and Fractures Under 10x loupe: irregular internal surfaces that catch light and appear bright, wing-like, or… Fractures Fingerprint Inclusions Under 10x loupe: curved or wavy lines of tiny dots forming patterns that look… Clouds Pinpoint Clouds Under 10x loupe: concentrations of extremely tiny bright dots that individually are too small… Multiphase Two-Phase Inclusions Under 10x loupe: a transparent irregular cavity containing both a liquid phase and a…
Identification

Instruments used

Dichroscope Reveals pleochroism, instantly eliminates singly-refractive stones 10x Loupe Your most-used instrument, start every examination here Polariscope Determines single vs. double refraction, quick and conclusive Refractometer Measures refractive index, the backbone of gem identification UV Lamp, Long Wave and Short Wave Fluorescence exposes treatments, synthetics, and origin