Vote for your favorite mineral in #MinCup26! - Quartz vs. Asagiite
It's a classic vs a newbie as the most common named mineral in the crust Quartz is up against an exceedingly-rare sea foam-green mineral discovered just a few years ago Asagiite.
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Offretite from
Devils Backbone, North Fork John Day River, Grant County, Oregon, USA


Classification
Species:Offretite
Formula:KCaMg(Si13Al5)O36 · 15H2O
Comments:Erionite not offretite?
The zeolite mineral species epitaxially overgrown on lévyne in all cases is identified as erionite (Passaglia et al., 1998).

Passaglia, E., Artioli, G., & Gualtieri, A. (1998). Crystal chemistry of the zeolites erionite and offretite. American Mineralogist, 83(5-6), 577-589.
Confirmation
Validity:Unconfirmed/Questioned
Data
Mineral Data:Click here to view Offretite data
Locality Data:Click here to view Devils Backbone, North Fork John Day River, Grant County, Oregon, USA
Data Identifiers
Mindat Occurrence Record ID:1076258
Long-form Identifier:1:3:1076258:9
GUID (UUID V4):0
Nearest other occurrences of Offretite
11.8km (7.3 miles) ⓘMiddle Fork Cliffs, Ritter, Grant County, Oregon, USA
15.0km (9.3 miles) ⓘRoadside Quarry, Ritter, Grant County, Oregon, USA
15.1km (9.4 miles) ⓘUpper Ritter Quarry, Ritter, Grant County, Oregon, USA
39.6km (24.6 miles) ⓘBurnt Cabin Creek, Spray, Wheeler County, Oregon, USA
52.5km (32.7 miles) ⓘBeech Creek Quarry, Mount Vernon, Grant County, Oregon, USA
References
(n.d.) Rudy Tschernich Zeolite Collection, Rice Museum.
 
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