Beryl

Emerald

Refractive Index: 1.5720–1.5765
Abbe Number: 69.2–69.7
Crystal System: Isotropic (cubic)
Formation: Natural
Dispersion Data: Measured (published fit)
Fits: 2

Refraction Fits

Fit #1

Shannon / Cauchy

$n$

n

= 1.5720

V_{D}

= 69.7

n^{2} = 1 + \frac{λ ^{2}}{0.6976 ( λ ^{2} - 0.008888 )}

Fit #2— Specimen fit

Shannon / Cauchy

$n$

n

= 1.5765

V_{D}

= 69.2

n^{2} = 1 + \frac{λ ^{2}}{0.6911 ( λ ^{2} - 0.008971 )}

Padre Paraiso, Minas Gerais

Absorption Specimens

Colombia, Boyacá Province, Gachalá

Colombia, Boyacá Province, Muzo

Colombia, Boyacá Province, Muzo

Russia, Ural Mountains Region