Red Beryl
Last updated: April 2026
Red beryl (bixbite) is colored by Mn²⁺ and found almost exclusively in the Wah Wah Mountains of Utah. Beryl RI/SG are the primary diagnostic tools. Faceted stones over 1 carat are very rare.
Red Beryl has a specific gravity of 2.68 and a refractive index of 1.564–1.574, with a Mohs hardness of 7.5–8.0. It is uniaxial −.
Physical & Optical Properties
Measured with a polariscope, a refractometer, a hydrostatic balance, a Chelsea filter, a UV torch, a loupe, a darkfield loupe and a spectroscope — step-by-step for each.
Through the refractometer
Drawn from the refractive index above, on a 1.40–1.81 scale. How to take this reading.
Related: Beryl Varieties
Key Differentiators
- Extremely rare — essentially restricted to Wah Wah Mountains, Utah; faceted stones over 1ct are exceptional
- Beryl RI (1.564–1.574) and SG (~2.68) clearly distinguish from ruby (RI 1.762, SG 4.00) and red spinel (isotropic, RI 1.718)
- Chelsea filter inert — Mn²⁺ coloring does not produce Chelsea reaction
- Strong dichroism (red/orange-red) — distinguishes from isotropic red spinel
- Almost always heavily included with growth tubes; clean large stones essentially nonexistent
Natural vs. Synthetic
Synthetic red beryl is commercially available (Hydrothermal). Distinguishing natural from synthetic typically requires microscopic examination of internal features.
- Microscopy: Growth tubes, two-phase inclusions, crystal inclusions typical of pegmatite/rhyolite origin; highly included Synthetic: Hydrothermal synthetic shows two-phase inclusions along growth planes (chevron/nailhead spicule pattern), more inclusion-free zones, fewer crystal inclusions
Loupewise Pro includes a two-phase natural vs. synthetic testing protocol for Red Beryl.
Common Simulants
- Ruby: Corundum RI 1.762–1.770, SG 4.00; Chelsea red from Cr; strong dichroism; much higher RI and density than red beryl
- Red Spinel: Isotropic (SR), RI 1.718, SG 3.60; no pleochroism; Chelsea may show red; much higher RI than red beryl
- Rubellite Tourmaline: RI 1.624–1.644 (higher than red beryl), birefringence 0.018 (much higher), SG 3.06; growth tubes; different RI range
- Red Glass: Isotropic; gas bubbles, swirl marks; no natural inclusions; variable RI
Treatments
- Heat Treatment (rare — generally not practiced)
Measurement Guides
Identifying a red beryl? Loupewise walks through these tests in order — RI, SG, fluorescence, and more.
Try Loupewise Free →Studying for the GIA, FGA, or FEEG practical? Red Beryl is one of the 132 species in Loupewise’s drill and exam pool — practice identifying it from its measured properties under timed exam conditions.
Practice exams →