Rare Mineral
Jeremejevite
Rare aluminum borate mineral
Blue
Colorless
Optical characteristics
- Ref. index
- 1.64 – 1.653
- Luster
- Vitreous
- Pleochroism
- Moderate Variable depending on transparency, orientation, and variety.
- Fluorescence
- Variable to inert.
Source localities
Myanmar
Myanmar: Mogok Valley
Premium
★ Top Source
Classic source for ruby, sapphire, spinel and other collector gems.
Tajikistan
Tajikistan: Kuh-i-Lal / Badakhshan
Premium
★ Top Source
Historic source of spinel and gem material.
Namibia
Namibia: Erongo / Green Dragon area
Notable
Known for demantoid, spessartite and collector minerals.
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…
Instruments used
Dichroscope
Reveals pleochroism, instantly eliminates singly-refractive stones
Immersion Microscope
See every internal detail clearly, the professional standard
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