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Compare Minerals

Put any two minerals side by side — formula, structure, hardness, density and more. Type to search each slot.

Mineral A

VS

Mineral B

O

Name

—

Na(Fe²⁺₂Al)Al₆(Si₆O₁₈)(BO₃)₃(OH)₃O

Formula

—

Mineral Species

Entry type

—

Silicates

Chemical class

—

Hexagonal

Crystal system

—

7

Mohs hardness

—

3.17–3.19

Specific gravity

—

Pale gray

Streak

—

Vitreous

Luster

—

None

Cleavage

—

R3m

Space group

—

Tourmaline

Structural group

—

Osrl · Approved

IMA

—

2011

Named in

—

Greenish to brownish black

Typical colors

—

Na · Fe · Al · Si · O · B · H

Elements

—