Emerald

Related: Beryl Varieties

AquamarineGosheniteHeliodorMorganiteRed Beryl

Key Differentiators

• Shows red through Chelsea filter
• Characteristic three-phase inclusions
• Low RI and SG

Natural vs. Synthetic

Synthetic emerald is commercially available (Flux (Chatham, Gilson), Hydrothermal (Biron, Linde/Regency, Pool), Lechleitner overgrowth). Distinguishing natural from synthetic typically requires microscopic examination of internal features.

• Microscopy — inclusions: Three-phase inclusions (solid+liquid+gas in one cavity) are definitive for Colombian origin. Also: jagged two-phase inclusions, actinolite needles, biotite, pyrite, irregular fingerprint fractures. Synthetic: Flux (Chatham/Gilson): wispy/cottony flux veils, platinum crystals (metallic reflective platelets), chevron growth patterns (Gilson diagnostic). Hydrothermal (Biron/Linde): nail-head spicules/chrysanthemum inclusions, comma-shaped two-phase inclusions, parallel growth tubes along c-axis. Lechleitner: visible interface between pale natural core and synthetic overgrowth; natural inclusions in core, hydrothermal features in rim.
• UV Fluorescence: Inert to weak red (LWUV). Iron-rich origins (Brazil, Russia) are typically inert. Low-iron Colombian may show weak red. Synthetic: Flux and hydrothermal synthetics: moderate to strong red (LWUV). High Cr content and near-zero Fe produces strong response. Strong red fluorescence is a red flag — but not conclusive alone.
• Chelsea Filter: Weak to moderate pinkish-red. Iron quenches the response. Synthetic: Strong vibrant red or purplish-red. Synthetics are high-Cr / low-Fe, producing a strong filter reaction. Some fine low-iron Colombian naturals can also show strong red — use microscopy to confirm.
• RI: nω 1.565–1.602; SG 2.67–2.78. Synthetic: Flux (Chatham/Gilson): RI nω ~1.560–1.564 (lower than natural — diagnostic). SG ~2.62–2.67. Hydrothermal (Biron/Linde): RI nω ~1.578–1.585 (higher end). SG ~2.67–2.75. A consistently low RI (<1.565) indicates flux synthetic; high RI (>1.580) suggests hydrothermal.

Common Simulants

• Green Tourmaline: Uniaxial negative DR; stronger dichroism; higher RI (1.624–1.644); SG 3.06; no red through Chelsea filter.
• Green Glass: Isotropic; gas bubbles, swirl marks or flow lines under loupe; no dichroism; conchoidal fracture.
• Synthetic green spinel: Isotropic SR; RI ~1.727; Chelsea filter typically red (synthetic spinel fluoresces); no dichroism.
• Tsavorite Garnet: Isotropic SR; no dichroism; RI ~1.740; SG 3.61; Chelsea filter inert (no red).

Commonly Confused With

Commonly confused with: Tourmaline, Glass, Synthetic Spinel, Tsavorite Garnet, Chrome Diopside, Fluorite, YAG.

Treatments

• Cedar Oil / Natural Oil Filling
• Synthetic Resin Filling (Opticon, Permasafe)
• Epoxy Resin Filling (permanent)

Price Context

Price context is approximate. GemID is not an appraisal tool. Results are indicators, not certified valuations.

Related Comparisons

Emerald Vs TsavoriteNatural Vs Synthetic Emerald

Measurement Guides

How to Identify a GemstoneHow to Measure Specific GravityHow to Use a RefractometerUV Fluorescence Testing