Sorosilicate
Danburite
Colorless to pale yellow, rarely pink; high clarity typical
Colorless
Pink
Yellow
Optical characteristics
- Ref. index
- 1.63 – 1.636
- Birefringence
- 0.006
- Luster
- Vitreous
- Pleochroism
- None Typically none in colorless specimens; pink may show weak dichroism.
- Fluorescence
- Strong blue to blue-green fluorescence under LW UV — a reliable identifier.
Source localities
Myanmar
Myanmar: Mogok Valley
Premium
★ Top Source
Classic source for ruby, sapphire, spinel and other collector gems; Myanmar danburite is prized for clarity.
Russia
Russia: Ural Mountains / Siberia
Significant
Classic source for alexandrite, demantoid, diamond and nephrite.
Tanzania
Tanzania: Merelani Hills
Significant
Sole source of tanzanite worldwide; also produces tsavorite, ruby, sapphire and rare collector gems.
Mexico
Mexico: Querétaro / Jalisco / Sonora / Coahuila
Significant
★ Top Source
Known for fire opal, turquoise, amber and collector minerals; San Luis Potosi is a classic danburite source.
Switzerland
Switzerland: alpine quartz localities
Significant
Known for rock crystal and alpine minerals; Swiss Alps produce collector danburite.
Inclusions & features
Crystals Crystal Inclusions
Under 10x loupe: solid, well-formed mineral crystals trapped inside the host gem. They may…
Fractures Fingerprint Inclusions
Under 10x loupe: curved or wavy lines of tiny dots forming patterns that look…
Crystals Negative Crystals
Under 10x loupe: an empty cavity that has the geometric shape of the host…
Multiphase Two-Phase Inclusions
Under 10x loupe: a transparent irregular cavity containing both a liquid phase and a…
Instruments used
Refractometer
Measures refractive index, the backbone of gem identification
10x Loupe
Your most-used instrument, start every examination here
Polariscope
Determines single vs. double refraction, quick and conclusive
UV Lamp, Long Wave and Short Wave
Fluorescence exposes treatments, synthetics, and origin
Hydrostatic Scale
Measures specific gravity, works even on opaque stones