Verdelite Gem Guide and Properties Chart

Verdelite refers to green elbaite tourmaline that does not contain chromium. Although green is a common color of tourmaline, not all greens are valued equally. Verdelite gems come in varying shades of green; some so saturated that direct light is necessary to see the body color. From lush grass-green to electric yellow-green to olive, and even bluish green, there is a verdelite gem to fit all tastes.

General Information

Classification
Optical Properties
Characteristic Physical Properties
Chemistry & Crystallography

Common Name

Verdelite

Species

Tourmaline

Transparency

Transparent - Opaque

Dispersion

Strength: Moderate Fire Value: 0.017

Refractive Index

1.610-1.665

Birefringence

0.018-0.020

Optic Character

Uniaxial

Optic Sign

Negative

Polariscope Reaction

Doubly Refractive (DR)

Fluorescence

SWUV: Variable
LWUV: Variable

Pleochroism

Dichroic, strong dark green and yellow-green

Hardness

7-7.5

Streak

White

Specific Gravity

3.000-3.260 Typical:3.060

Toughness

Good

Inclusions

Verdelite tourmaline is Type I clarity stone. Stones might contain liquid and gas inclusions that are long and thin, reflective gas-filled fractures and color zoning.

Luster

Vitreous

Stability

Very Good

Fracture

Conchoidal, Subconchoidal, Uneven

Cleavage

Poor, in two directions

Chemical Name

Complex boro-silicate of Al, Li and Na

Chemical Formula

Na(Li₁.₅Al₁.₅)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃(OH)

Crystal System

Trigonal

Chemistry Classification

Silicate

Verdelite Colors

Green
Green
Green
Green
Green

Alternate Names

Verdelith

Countries of Origin

Afghanistan; Russian Federation; Czechia; Sri Lanka; Japan; United States of America; Madagascar; Kenya; United Kingdom of Great Britain and Northern Ireland; India; Sweden; Mozambique; Unknown; China; Finland; Brazil; Italy; Australia; France; Nigeria; Germany; Tajikistan