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Poás Volcano, Sarchí Canton, Alajuela Province, Costa Ricai
Regional Level Types
Poás VolcanoStratovolcano (Active)
Sarchí CantonCanton
Alajuela ProvinceProvince
Costa RicaCountry

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PhotosMapsSearch
02817430017272048816753.jpg
Sampling a crater pool

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
05014570017272048827200.jpg
"Eye" in Poás crater wall

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
05192460017272048836458.jpg
View from crater floor to crater rim

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
03534520017439203704356.jpg
Crater of Poás, 1985, showing the layered structure that defines a stratovolcano

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
02817430017272048816753.jpg
Sampling a crater pool

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
05014570017272048827200.jpg
"Eye" in Poás crater wall

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
05192460017272048836458.jpg
View from crater floor to crater rim

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
01676440017438579743896.jpg
Crater of Poás, 1985, showing the layered structure that defines a stratovolcano

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
02817430017272048816753.jpg
Sampling a crater pool

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
00709750017272048887435.jpg
"Eye" in Poás crater wall

Poás Volcano, Sarchí Canton, Alajuela Province, Costa Rica
Latitude & Longitude (WGS84):
10° 11' 55'' North , 84° 13' 57'' West
Latitude & Longitude (decimal):
10.19883,-84.23266
GRN:
N07W59
Type:
Stratovolcano (Active) - last checked 2023
Köppen climate type:
Am : Tropical monsoon climate
Mindat Locality ID:
301676
Long-form identifier:
mindat:1:2:301676:6
GUID (UUID V4):
0
Name(s) in local language(s):
(Spanish) Volcán Poás


Poás is a large, active stratovolcano located about 19 km north of Alajuela in Alajuela Province, Costa Rica. The surrounding area is protected by the Poás Volcano National Park. Extensive emission of hydrogen sulfide and sulfur dioxide gases for decades has defoliated a large area west of the active crater, and the park is frequently closed to visitors due to poor air quality. Due to the ongoing risk of further violent activity without sufficient seismic warning to enable safe evacuation, the park was closed to visitors for a time following significant eruptions in April 2017. Limited visitation had resumed as of December 2018.

The active crater, at approximately 300 m in diameter one of the largest active volcanic craters in the world, is occupied by a rain-fed lake rendered acidic by fumaroles on the floor of the crater. A period of increased activity in the late 1980s increased the temperature of the lake from 40°C to 85°C, and as a consequence the lake largely evaporated for a time except for a few small, highly concentrated pools whose pH was measured as low as 0.2, one of the most acidic conditions to exist anywhere on Earth. The crater photos by E.L. Clopton on this page were taken during that time. In the early 1990s, the temperature decreased enough to allow the crater to refill with water. The lake remains warm and is disturbed from time to time by phreatic eruptions, jets of steam formed by lake water seeping into hot fissures in the crater floor.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Mineral List


49 valid minerals. 1 erroneous literature entry.

Rock Types Recorded

Note: data is currently VERY limited. Please bear with us while we work towards adding this information!

Select Rock List Type

Alphabetical List Tree Diagram

Detailed Mineral List:

ⓘ Alunite
Formula: KAl3(SO4)2(OH)6
ⓘ Alunogen
Formula: Al2(SO4)3 · 17H2O
ⓘ Anatase
Formula: TiO2
ⓘ Anhydrite
Formula: CaSO4
ⓘ Ankerite
Formula: Ca(Fe2+,Mg)(CO3)2
ⓘ Apjohnite
Formula: Mn2+Al2(SO4)4 · 22H2O
ⓘ Augite
Formula: (CaxMgyFez)(Mgy1Fez1)Si2O6
ⓘ 'Brewsterite Subgroup'
ⓘ Carobbiite
Formula: KF
ⓘ 'Chabazite'
ⓘ Chabazite-Ca
Formula: (Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
ⓘ Copiapite
Formula: Fe2+Fe3+4(SO4)6(OH)2 · 20H2O
ⓘ Cowlesite
Formula: CaAl2Si3O10 · 6H2O
ⓘ Cristobalite
Formula: SiO2
ⓘ Enstatite
Formula: Mg2Si2O6
ⓘ Epsomite
Formula: MgSO4 · 7H2O
ⓘ 'Fayalite-Forsterite Series'
ⓘ Goethite
Formula: Fe3+O(OH)
ⓘ Greigite
Formula: Fe2+Fe3+2S4
ⓘ Gypsum
Formula: CaSO4 · 2H2O
ⓘ Halite
Formula: NaCl
ⓘ Halloysite
Formula: Al2(Si2O5)(OH)4
ⓘ Halotrichite
Formula: FeAl2(SO4)4 · 22H2O
ⓘ Hematite
Formula: Fe2O3
ⓘ 'Hornblende Root Name Group'
Formula: ◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
ⓘ Huangite
Formula: Ca0.5Al3(SO4)2(OH)6
ⓘ Hydrokenoralstonite
Formula: Na0.5(Al,Mg)2(F,OH)6 · H2O
ⓘ Jarosite
Formula: KFe3+3(SO4)2(OH)6
ⓘ Kaolinite
Formula: Al2(Si2O5)(OH)4
ⓘ Khademite
Formula: Al(SO4)F · 5H2O
ⓘ Kogarkoite
Formula: Na3(SO4)F
ⓘ Magnesiocopiapite
Formula: MgFe3+4(SO4)6(OH)2 · 20H2O
ⓘ Magnetite
Formula: Fe2+Fe3+2O4
ⓘ Magnetite var. Titanium-bearing Magnetite
Formula: Fe2+(Fe3+,Ti)2O4
ⓘ Meta-alunogen
Formula: Al2(SO4)3 · 12H2O
ⓘ Montmorillonite
Formula: (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
ⓘ Mordenite
Formula: (Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
ⓘ 'Native Magnesium'
Formula: Mg
ⓘ Native Sulphur
Formula: S8
ⓘ 'Natroalunite-2c'
Formula: (Na,Ca0.5,K)Al3(SO4)2(OH)6
ⓘ Pertlikite
Formula: K2(Fe2+,Mg)2(Mg,Fe3+)4Fe3+2Al(SO4)12 · 18H2O
ⓘ Phillipsite-K
Formula: (K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
ⓘ 'Phillipsite Subgroup'
Formula: (Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
ⓘ Pickeringite
Formula: MgAl2(SO4)4 · 22H2O
ⓘ 'Plagioclase'
Formula: (Na,Ca)[(Si,Al)AlSi2]O8
ⓘ Pyrite
Formula: FeS2
ⓘ 'Pyroxene Group'
Formula: ADSi2O6
ⓘ Quartz
Formula: SiO2
ⓘ Rostite
Formula: Al(SO4)(OH) · 5H2O
ⓘ Römerite
Formula: Fe2+Fe3+2(SO4)4 · 14H2O
ⓘ Rutile
Formula: TiO2
ⓘ Sauconite
Formula: Na0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
ⓘ 'Smectite Group'
Formula: A0.3D2-3[T4O10]Z2 · nH2O
ⓘ Sofiite
Formula: Zn2(SeO3)Cl2
ⓘ 'Tennantite Subgroup'
Formula: Cu6(Cu4C2+2)As4S12S
ⓘ Tridymite
Formula: SiO2
ⓘ Tychite
Formula: Na6Mg2(CO3)4(SO4)
ⓘ Ulvöspinel
Formula: TiFe2+2O4
ⓘ Voltaite
Formula: K2Fe2+5Fe3+3Al(SO4)12 · 18H2O
ⓘ Woodhouseite
Formula: CaAl3(PO4)(SO4)(OH)6
ⓘ Wurtzite
Formula: (Zn,Fe)S

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
ⓘ'Native Magnesium' ?1.AB.Mg
ⓘNative Sulphur1.CC.05S8
Group 2 - Sulphides and Sulfosalts
ⓘWurtzite2.CB.45(Zn,Fe)S
ⓘGreigite2.DA.05Fe2+Fe3+2S4
ⓘPyrite2.EB.05aFeS2
ⓘ'Tennantite Subgroup'2.GB.05Cu6(Cu4C2+2)As4S12S
Group 3 - Halides
ⓘCarobbiite3.AA.20KF
ⓘHalite3.AA.20NaCl
ⓘHydrokenoralstonite3.CF.05 Na0.5(Al,Mg)2(F,OH)6 · H2O
Group 4 - Oxides and Hydroxides
ⓘGoethite4.00.Fe3+O(OH)
ⓘMagnetite4.BB.05Fe2+Fe3+2O4
ⓘvar. Titanium-bearing Magnetite4.BB.05Fe2+(Fe3+,Ti)2O4
ⓘUlvöspinel4.BB.05TiFe2+2O4
ⓘHematite4.CB.05Fe2O3
ⓘQuartz4.DA.05SiO2
ⓘTridymite4.DA.10SiO2
ⓘCristobalite4.DA.15SiO2
ⓘRutile4.DB.05TiO2
ⓘAnatase4.DD.05TiO2
ⓘSofiite4.JG.15Zn2(SeO3)Cl2
Group 5 - Nitrates and Carbonates
ⓘAnkerite5.AB.10Ca(Fe2+,Mg)(CO3)2
ⓘTychite5.BF.05Na6Mg2(CO3)4(SO4)
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘAnhydrite7.AD.30CaSO4
ⓘAlunite7.BC.10KAl3(SO4)2(OH)6
ⓘHuangite7.BC.10Ca0.5Al3(SO4)2(OH)6
ⓘJarosite7.BC.10KFe3+3(SO4)2(OH)6
ⓘ'Natroalunite-2c'7.BC.10(Na,Ca0.5,K)Al3(SO4)2(OH)6
ⓘKogarkoite7.BD.15Na3(SO4)F
ⓘEpsomite7.CB.40MgSO4 · 7H2O
ⓘAlunogen7.CB.45Al2(SO4)3 · 17H2O
ⓘMeta-alunogen7.CB.45Al2(SO4)3 · 12H2O
ⓘRömerite7.CB.75Fe2+Fe3+2(SO4)4 · 14H2O
ⓘApjohnite7.CB.85Mn2+Al2(SO4)4 · 22H2O
ⓘHalotrichite7.CB.85FeAl2(SO4)4 · 22H2O
ⓘPickeringite7.CB.85MgAl2(SO4)4 · 22H2O
ⓘVoltaite7.CC.25K2Fe2+5Fe3+3Al(SO4)12 · 18H2O
ⓘPertlikite7.CC.25K2(Fe2+,Mg)2(Mg,Fe3+)4Fe3+2Al(SO4)12 · 18H2O
ⓘGypsum7.CD.40CaSO4 · 2H2O
ⓘKhademite7.DB.10Al(SO4)F · 5H2O
ⓘRostite7.DB.10Al(SO4)(OH) · 5H2O
ⓘCopiapite7.DB.35Fe2+Fe3+4(SO4)6(OH)2 · 20H2O
ⓘMagnesiocopiapite7.DB.35MgFe3+4(SO4)6(OH)2 · 20H2O
Group 8 - Phosphates, Arsenates and Vanadates
ⓘWoodhouseite8.BL.05CaAl3(PO4)(SO4)(OH)6
Group 9 - Silicates
ⓘEnstatite9.DA.05Mg2Si2O6
ⓘAugite9.DA.15(CaxMgyFez)(Mgy1Fez1)Si2O6
ⓘMontmorillonite9.EC.40(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
ⓘSauconite9.EC.45Na0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
ⓘKaolinite9.ED.05Al2(Si2O5)(OH)4
ⓘHalloysite9.ED.10Al2(Si2O5)(OH)4
ⓘPhillipsite-K9.GC.10(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
ⓘChabazite-Ca9.GD.10(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
ⓘMordenite9.GD.35(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
ⓘCowlesite9.GG.05CaAl2Si3O10 · 6H2O
Unclassified
ⓘ'Brewsterite Subgroup'-
ⓘ'Chabazite'-
ⓘ'Phillipsite Subgroup'-(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
ⓘ'Fayalite-Forsterite Series'-
ⓘ'Hornblende Root Name Group'-◻Ca2(Z2+4Z3+)(AlSi7O22)(OH,F,Cl)2
ⓘ'Plagioclase'-(Na,Ca)[(Si,Al)AlSi2]O8
ⓘ'Pyroxene Group'-ADSi2O6
ⓘ'Smectite Group'-A0.3D2-3[T4O10]Z2 · nH2O

List of minerals for each chemical element

HHydrogen
Hⓘ AluniteKAl3(SO4)2(OH)6
Hⓘ AlunogenAl2(SO4)3 · 17H2O
Hⓘ ApjohniteMn2+Al2(SO4)4 · 22H2O
Hⓘ CopiapiteFe2+Fe43+(SO4)6(OH)2 · 20H2O
Hⓘ CowlesiteCaAl2Si3O10 · 6H2O
Hⓘ EpsomiteMgSO4 · 7H2O
Hⓘ GoethiteFe3+O(OH)
Hⓘ GypsumCaSO4 · 2H2O
Hⓘ HalloysiteAl2(Si2O5)(OH)4
Hⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Hⓘ HuangiteCa0.5Al3(SO4)2(OH)6
Hⓘ JarositeKFe33+(SO4)2(OH)6
Hⓘ KaoliniteAl2(Si2O5)(OH)4
Hⓘ KhademiteAl(SO4)F · 5H2O
Hⓘ MagnesiocopiapiteMgFe43+(SO4)6(OH)2 · 20H2O
Hⓘ Meta-alunogenAl2(SO4)3 · 12H2O
Hⓘ Natroalunite-2c(Na,Ca0.5,K)Al3(SO4)2(OH)6
Hⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Hⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Hⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Hⓘ PickeringiteMgAl2(SO4)4 · 22H2O
Hⓘ Hydrokenoralstonite Na0.5(Al,Mg)2(F,OH)6 · H2O
Hⓘ RömeriteFe2+Fe23+(SO4)4 · 14H2O
Hⓘ RostiteAl(SO4)(OH) · 5H2O
Hⓘ SauconiteNa0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
Hⓘ VoltaiteK2Fe52+Fe33+Al(SO4)12 · 18H2O
Hⓘ WoodhouseiteCaAl3(PO4)(SO4)(OH)6
Hⓘ Chabazite-Ca(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
Hⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Hⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Hⓘ Smectite GroupA0.3D2-3[T4O10]Z2 · nH2O
Hⓘ PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe23+Al(SO4)12 · 18H2O
CCarbon
Cⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Cⓘ TychiteNa6Mg2(CO3)4(SO4)
OOxygen
Oⓘ AluniteKAl3(SO4)2(OH)6
Oⓘ AlunogenAl2(SO4)3 · 17H2O
Oⓘ AnataseTiO2
Oⓘ AnhydriteCaSO4
Oⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Oⓘ ApjohniteMn2+Al2(SO4)4 · 22H2O
Oⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Oⓘ CopiapiteFe2+Fe43+(SO4)6(OH)2 · 20H2O
Oⓘ CowlesiteCaAl2Si3O10 · 6H2O
Oⓘ CristobaliteSiO2
Oⓘ EnstatiteMg2Si2O6
Oⓘ EpsomiteMgSO4 · 7H2O
Oⓘ GoethiteFe3+O(OH)
Oⓘ GypsumCaSO4 · 2H2O
Oⓘ HalloysiteAl2(Si2O5)(OH)4
Oⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Oⓘ HematiteFe2O3
Oⓘ HuangiteCa0.5Al3(SO4)2(OH)6
Oⓘ JarositeKFe33+(SO4)2(OH)6
Oⓘ KaoliniteAl2(Si2O5)(OH)4
Oⓘ KhademiteAl(SO4)F · 5H2O
Oⓘ KogarkoiteNa3(SO4)F
Oⓘ MagnesiocopiapiteMgFe43+(SO4)6(OH)2 · 20H2O
Oⓘ MagnetiteFe2+Fe23+O4
Oⓘ Meta-alunogenAl2(SO4)3 · 12H2O
Oⓘ Natroalunite-2c(Na,Ca0.5,K)Al3(SO4)2(OH)6
Oⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Oⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Oⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Oⓘ PickeringiteMgAl2(SO4)4 · 22H2O
Oⓘ QuartzSiO2
Oⓘ Hydrokenoralstonite Na0.5(Al,Mg)2(F,OH)6 · H2O
Oⓘ RömeriteFe2+Fe23+(SO4)4 · 14H2O
Oⓘ RostiteAl(SO4)(OH) · 5H2O
Oⓘ RutileTiO2
Oⓘ SauconiteNa0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
Oⓘ SofiiteZn2(SeO3)Cl2
Oⓘ Magnetite var. Titanium-bearing MagnetiteFe2+(Fe3+,Ti)2O4
Oⓘ TridymiteSiO2
Oⓘ TychiteNa6Mg2(CO3)4(SO4)
Oⓘ UlvöspinelTiFe22+O4
Oⓘ VoltaiteK2Fe52+Fe33+Al(SO4)12 · 18H2O
Oⓘ WoodhouseiteCaAl3(PO4)(SO4)(OH)6
Oⓘ Chabazite-Ca(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
Oⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Oⓘ Fayalite-Forsterite Series
Oⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Oⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Oⓘ Pyroxene GroupADSi2O6
Oⓘ Smectite GroupA0.3D2-3[T4O10]Z2 · nH2O
Oⓘ PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe23+Al(SO4)12 · 18H2O
FFluorine
Fⓘ CarobbiiteKF
Fⓘ KhademiteAl(SO4)F · 5H2O
Fⓘ KogarkoiteNa3(SO4)F
Fⓘ Hydrokenoralstonite Na0.5(Al,Mg)2(F,OH)6 · H2O
Fⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
NaSodium
Naⓘ HaliteNaCl
Naⓘ KogarkoiteNa3(SO4)F
Naⓘ Natroalunite-2c(Na,Ca0.5,K)Al3(SO4)2(OH)6
Naⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Naⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Naⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Naⓘ Hydrokenoralstonite Na0.5(Al,Mg)2(F,OH)6 · H2O
Naⓘ SauconiteNa0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
Naⓘ TychiteNa6Mg2(CO3)4(SO4)
Naⓘ Chabazite-Ca(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
Naⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Naⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
MgMagnesium
Mgⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Mgⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Mgⓘ EnstatiteMg2Si2O6
Mgⓘ EpsomiteMgSO4 · 7H2O
Mgⓘ MagnesiocopiapiteMgFe43+(SO4)6(OH)2 · 20H2O
Mgⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Mgⓘ PickeringiteMgAl2(SO4)4 · 22H2O
Mgⓘ Hydrokenoralstonite Na0.5(Al,Mg)2(F,OH)6 · H2O
Mgⓘ TychiteNa6Mg2(CO3)4(SO4)
Mgⓘ Fayalite-Forsterite Series
Mgⓘ PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe23+Al(SO4)12 · 18H2O
Mgⓘ Native MagnesiumMg
AlAluminium
Alⓘ AluniteKAl3(SO4)2(OH)6
Alⓘ AlunogenAl2(SO4)3 · 17H2O
Alⓘ ApjohniteMn2+Al2(SO4)4 · 22H2O
Alⓘ CowlesiteCaAl2Si3O10 · 6H2O
Alⓘ HalloysiteAl2(Si2O5)(OH)4
Alⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Alⓘ HuangiteCa0.5Al3(SO4)2(OH)6
Alⓘ KaoliniteAl2(Si2O5)(OH)4
Alⓘ KhademiteAl(SO4)F · 5H2O
Alⓘ Meta-alunogenAl2(SO4)3 · 12H2O
Alⓘ Natroalunite-2c(Na,Ca0.5,K)Al3(SO4)2(OH)6
Alⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Alⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Alⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Alⓘ PickeringiteMgAl2(SO4)4 · 22H2O
Alⓘ Hydrokenoralstonite Na0.5(Al,Mg)2(F,OH)6 · H2O
Alⓘ RostiteAl(SO4)(OH) · 5H2O
Alⓘ SauconiteNa0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
Alⓘ VoltaiteK2Fe52+Fe33+Al(SO4)12 · 18H2O
Alⓘ WoodhouseiteCaAl3(PO4)(SO4)(OH)6
Alⓘ Chabazite-Ca(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
Alⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Alⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Alⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Alⓘ PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe23+Al(SO4)12 · 18H2O
SiSilicon
Siⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Siⓘ CowlesiteCaAl2Si3O10 · 6H2O
Siⓘ CristobaliteSiO2
Siⓘ EnstatiteMg2Si2O6
Siⓘ HalloysiteAl2(Si2O5)(OH)4
Siⓘ KaoliniteAl2(Si2O5)(OH)4
Siⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Siⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Siⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Siⓘ QuartzSiO2
Siⓘ SauconiteNa0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
Siⓘ TridymiteSiO2
Siⓘ Chabazite-Ca(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
Siⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Siⓘ Fayalite-Forsterite Series
Siⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Siⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
Siⓘ Pyroxene GroupADSi2O6
PPhosphorus
Pⓘ WoodhouseiteCaAl3(PO4)(SO4)(OH)6
SSulfur
Sⓘ AluniteKAl3(SO4)2(OH)6
Sⓘ AlunogenAl2(SO4)3 · 17H2O
Sⓘ AnhydriteCaSO4
Sⓘ ApjohniteMn2+Al2(SO4)4 · 22H2O
Sⓘ CopiapiteFe2+Fe43+(SO4)6(OH)2 · 20H2O
Sⓘ EpsomiteMgSO4 · 7H2O
Sⓘ GreigiteFe2+Fe23+S4
Sⓘ GypsumCaSO4 · 2H2O
Sⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Sⓘ HuangiteCa0.5Al3(SO4)2(OH)6
Sⓘ JarositeKFe33+(SO4)2(OH)6
Sⓘ KhademiteAl(SO4)F · 5H2O
Sⓘ KogarkoiteNa3(SO4)F
Sⓘ MagnesiocopiapiteMgFe43+(SO4)6(OH)2 · 20H2O
Sⓘ Meta-alunogenAl2(SO4)3 · 12H2O
Sⓘ Natroalunite-2c(Na,Ca0.5,K)Al3(SO4)2(OH)6
Sⓘ PickeringiteMgAl2(SO4)4 · 22H2O
Sⓘ PyriteFeS2
Sⓘ RömeriteFe2+Fe23+(SO4)4 · 14H2O
Sⓘ RostiteAl(SO4)(OH) · 5H2O
Sⓘ Native SulphurS8
Sⓘ Tennantite SubgroupCu6(Cu4C22+)As4S12S
Sⓘ TychiteNa6Mg2(CO3)4(SO4)
Sⓘ VoltaiteK2Fe52+Fe33+Al(SO4)12 · 18H2O
Sⓘ WoodhouseiteCaAl3(PO4)(SO4)(OH)6
Sⓘ Wurtzite(Zn,Fe)S
Sⓘ PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe23+Al(SO4)12 · 18H2O
ClChlorine
Clⓘ HaliteNaCl
Clⓘ SofiiteZn2(SeO3)Cl2
Clⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
KPotassium
Kⓘ AluniteKAl3(SO4)2(OH)6
Kⓘ CarobbiiteKF
Kⓘ JarositeKFe33+(SO4)2(OH)6
Kⓘ Natroalunite-2c(Na,Ca0.5,K)Al3(SO4)2(OH)6
Kⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Kⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Kⓘ VoltaiteK2Fe52+Fe33+Al(SO4)12 · 18H2O
Kⓘ Chabazite-Ca(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
Kⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Kⓘ PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe23+Al(SO4)12 · 18H2O
CaCalcium
Caⓘ AnhydriteCaSO4
Caⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Caⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Caⓘ CowlesiteCaAl2Si3O10 · 6H2O
Caⓘ GypsumCaSO4 · 2H2O
Caⓘ HuangiteCa0.5Al3(SO4)2(OH)6
Caⓘ Natroalunite-2c(Na,Ca0.5,K)Al3(SO4)2(OH)6
Caⓘ Mordenite(Na2,Ca,K2)4(Al8Si40)O96 · 28H2O
Caⓘ Montmorillonite(Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2 · nH2O
Caⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Caⓘ WoodhouseiteCaAl3(PO4)(SO4)(OH)6
Caⓘ Chabazite-Ca(Ca,K2,Na2)2[Al2Si4O12]2 · 12H2O
Caⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Caⓘ Hornblende Root Name Group◻Ca2(Z42+Z3+)(AlSi7O22)(OH,F,Cl)2
Caⓘ Plagioclase(Na,Ca)[(Si,Al)AlSi2]O8
TiTitanium
Tiⓘ AnataseTiO2
Tiⓘ RutileTiO2
Tiⓘ Magnetite var. Titanium-bearing MagnetiteFe2+(Fe3+,Ti)2O4
Tiⓘ UlvöspinelTiFe22+O4
MnManganese
Mnⓘ ApjohniteMn2+Al2(SO4)4 · 22H2O
FeIron
Feⓘ AnkeriteCa(Fe2+,Mg)(CO3)2
Feⓘ Augite(CaxMgyFez)(Mgy1Fez1)Si2O6
Feⓘ CopiapiteFe2+Fe43+(SO4)6(OH)2 · 20H2O
Feⓘ GoethiteFe3+O(OH)
Feⓘ GreigiteFe2+Fe23+S4
Feⓘ HalotrichiteFeAl2(SO4)4 · 22H2O
Feⓘ HematiteFe2O3
Feⓘ JarositeKFe33+(SO4)2(OH)6
Feⓘ MagnesiocopiapiteMgFe43+(SO4)6(OH)2 · 20H2O
Feⓘ MagnetiteFe2+Fe23+O4
Feⓘ PyriteFeS2
Feⓘ RömeriteFe2+Fe23+(SO4)4 · 14H2O
Feⓘ Magnetite var. Titanium-bearing MagnetiteFe2+(Fe3+,Ti)2O4
Feⓘ UlvöspinelTiFe22+O4
Feⓘ VoltaiteK2Fe52+Fe33+Al(SO4)12 · 18H2O
Feⓘ Wurtzite(Zn,Fe)S
Feⓘ Fayalite-Forsterite Series
Feⓘ PertlikiteK2(Fe2+,Mg)2(Mg,Fe3+)4Fe23+Al(SO4)12 · 18H2O
CuCopper
Cuⓘ Tennantite SubgroupCu6(Cu4C22+)As4S12S
ZnZinc
Znⓘ SauconiteNa0.3Zn3((Si,Al)4O10)(OH)2 · 4H2O
Znⓘ SofiiteZn2(SeO3)Cl2
Znⓘ Wurtzite(Zn,Fe)S
AsArsenic
Asⓘ Tennantite SubgroupCu6(Cu4C22+)As4S12S
SeSelenium
Seⓘ SofiiteZn2(SeO3)Cl2
BaBarium
Baⓘ Phillipsite Subgroup(Ca0.5,K,Na,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O
Baⓘ Phillipsite-K(K,Na,Ca0.5,Ba0.5)4-7[Al4-7Si12-9O32] . 12H2O

Other Regions, Features and Areas containing this locality

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Panama PlateTectonic Plate

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References

Costa-Rica-Guide.com. Poas Volcano Tickets & Visitor Information. https://costa-rica-guide.com/nature/national-parks/poas-volcano-tickets-visitor-information/, accessed 12/2/2018.
Thorpe, R.S., Locke, C.A., Brown, G.C., Francis, P.W., and Randal, M. (1981) Magma chamber below Poàs volcano, Costa Rica. Journal of the Geological Society, 138, 367-373, https://doi.org/10.1144/gsjgs.138.3.0367
Prosser, J.T. and Carr, M.J. (1987) Poás volcano, Costa Rica: Geology of the summit region and spatial and temporal variations among the most recent lavas. Journal of Volcanology and Geothermal Research, 33(1-3), 131-146.
Brantley, S.L., Borgiatt, A., Rowe, G., Fernandez, J.F., and Reynolds, J.R. (1987) Poás volcano crater lake acts as a condenser for acid metal-rich brine (letter). Nature, 330, 470-472.
Barquero H.J. (1998) Volcán Poás. San Jose, Costa Rica: J. Barquero H. [Spanish and English].
Rymer, H., Locke, C.A., Brenes, J., and Williams-Jones, G. (2005) Magma plumbing processes for persistent activity at Poás volcano, Costa Rica. Geophysical Research Letters, 32(8), L08307. https://doi.org/10.1029/2004GL022284
Rodríguez, A., & van Bergen, M. J. (2017). Superficial alteration mineralogy in active volcanic systems: An example of Poás volcano, Costa Rica. Journal of Volcanology and Geothermal Research, 346, 54-80.
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