Formula: Cu₅(Si₂O₆)₂(OH)₂

Species: Silicates – (Inosilicates)

Colour: Light to dark blue.

Lustre: Silky

Hardness: 3½

Specific Gravity: 4.11

Crystal System: Orthorhombic

Name: Named after its discovery locality, the Shattuck Mine, Bisbee, Arizona, USA.

Type Locality: Shattuck Mine (Shattuck-Denn Mine; Shattuck-Arizona Mine; Denn Mine), Bisbee, Cochise County, Arizona – USA

A rare secondary copper silicate. May be confused with Plancheite.