| Fingerite | |
| Category: | Vanadate mineral |
| Formula: | β-Cu2V2O5 |
| Imasymbol: | Fgr[1] |
| Strunz: | 8.BB.80 |
| System: | Triclinic |
| Class: | Pinacoidal H-M symbol: |
| Symmetry: | P |
| Unit Cell: | a = 8.16, b = 8.27 c = 8.04 [Å]; α = 107.14° β = 91.39°, γ = 106.44°; Z = 1 |
| Color: | Black; medium gray in reflected light |
| Habit: | Subhedral or anhedral; equant or platelike; up to 150 μm |
| Cleavage: | None |
| Luster: | Metallic |
| Streak: | Dark reddish brown |
| Diaphaneity: | Opaque |
| Density: | 4.78 |
| Opticalprop: | Biaxial |
| Solubility: | Dissolves in water |
| References: | [2] [3] [4] |
Fingerite is a copper vanadate mineral with formula: β-Cu2V2O5. It was discovered as triclinic crystals occurring as volcanic sublimates around fumaroles in the crater of the Izalco Volcano, El Salvador.
Associated minerals include thenardite, euchlorine, stoiberite, shcherbinaite, ziesite, bannermanite, chalcocyanite and chalcanthite.[2] The mineral also dissolves in water.[5]
Fingerite is named for Dr. Larry W. Finger (b. 1940-2024[6]) of the Geophysical Laboratory, Carnegie Institution of Washington.