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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Opal from
Gralheira Mine, U.F Romãs Decermilo e Vila Longa, Sátão, Viseu, Portugal


Locality type:Mine
Classification
Species:Opal
Formula:SiO2 · nH2O
Confirmation
Validity:Confirmed
Confirmation Methods:Visually Identified
Data
Mineral Data:Click here to view Opal data
Locality Data:Click here to view Gralheira Mine, U.F Romãs Decermilo e Vila Longa, Sátão, Viseu, Portugal
Data Identifiers
Mindat Occurrence Record ID:1006850
Long-form Identifier:1:3:1006850:8
GUID (UUID V4):0
Nearest other occurrences of Opal
3.8km (2.4 miles) ⓘFonte Limeira quarry, U.F Romãs Decermilo e Vila Longa, Sátão, Viseu, Portugal
4.9km (3.0 miles) ⓘRomãs quarry, U.F Romãs Decermilo e Vila Longa, Sátão, Viseu, Portugal
9.2km (5.7 miles) ⓘAssunção Mine, Aldeia Nova, Ferreira de Aves, Sátão, Viseu, Portugal
11.6km (7.2 miles) ⓘPenedo da Cabeça quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
11.7km (7.2 miles) ⓘRatoeira quarry, U.F. Sequeiros e Gradiz, Aguiar da Beira, Guarda, Portugal
12.8km (8.0 miles) ⓘBom Sucesso No. 4 quarry, Tavares (Chãs; Várzea e Travanca), Mangualde, Viseu, Portugal
16.7km (10.4 miles) ⓘNossa Senhora da Esperança quarry, Quintela de Azurara, Mangualde, Viseu, Portugal
49.5km (30.8 miles) ⓘBendada Mines, Bendada, Sabugal, Guarda, Portugal
58.1km (36.1 miles) ⓘPortugal 1 & 2 quarries, Malpartida, Malpartida e Vale de Coelha, Almeida, Guarda, Portugal
73.4km (45.6 miles) ⓘPalhal Mine, Branca, Albergaria-a-Velha, Aveiro, Portugal
References
Alves, Pedro (n.d.) Personal communication.
 
and/or  
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