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(mineralogy) A rare mineral ZnAl₂O₄ in the spinel group.

Gahnite – Oxide minerals – Spinel group – Spinel structural group – ZnAl₂O₄ – Ghn – 4.BB.05 – Cubic – Hexoctahedral (m3m) – (4/m 3 2/m) – Fd3m – Dark green, bluish green, blue to indigo, yellow to brown – Typically octahedra, rarely as dodecahedra also massive to granular – Common on [111] produces striations – Indistinct parting on [111] – Conchoidal, uneven – 7.5–8.0 – Vitreous – Grey – Translucent to nearly opaque – 4.38–4.60 – Isotropic – N = 1.79–1.80.