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Stuart Creek Opal Diggings, Mulgaria, Pastoral Unincorporated Area, South Australia, Australia i
Regional Level Types
Stuart Creek Opal Diggings Diggings
Mulgaria Locality (Australia)
Pastoral Unincorporated Area Unincorporated Area
South Australia State
Australia Country

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Predictive Mineralogy

Latitude & Longitude (WGS84):

30° 5' 31'' South , 137° 14' 56'' East

Latitude & Longitude (decimal):

-30.09222,137.24889

Type:

Köppen climate type:

BWh : Hot deserts climate

Nearest Settlements:

Place	Population	Distance
Roxby Downs	4,055 (2011)	62.4km

Mindat Locality ID:

17662

Long-form identifier:

mindat:1:2:17662:5

GUID (UUID V4):

0

Intensive opal mines and workings are located around the margins of a mesa (locally called Split Hill) which is capped by silicified sediments. Deep bulldozer trenches, down to 20 m, have exposed the Tertiary and underlying Cretaceous sediments. Large masses and pans of silicified Tertiary sands extend laterally for 10 to 50 m.

Select Mineral List Type

Standard Detailed Gallery Strunz Chemical Elements

Commodity List

This is a list of exploitable or exploited mineral commodities recorded at this locality.

Mineral List

9 valid minerals.

Rock Types Recorded

Select Rock List Type

Alphabetical List Tree Diagram

ⓘ 'Pseudobreccia'

Detailed Mineral List:

Formula: TiO₂

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: CaCO₃

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: Fe³⁺O(OH)

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: CaSO₄ · 2H₂O

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: Fe₂O₃

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: Al₂(Si₂O₅)(OH)₄

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ 'Leucoxene'

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: KAl₂(AlSi₃O₁₀)(OH)₂

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Muscovite var. Illite

Formula: K_0.65Al_2.0[Al_0.65Si_3.35O₁₀](OH)₂

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: SiO₂ · nH₂O

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Opal var. Lussatite

Formula: SiO₂ · nH₂O

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Opal var. Opal Matrix

Formula: SiO₂ · nH₂O

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Opal var. Opal-C

Formula: SiO₂ · nH₂O

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Opal var. Opal-CT

Formula: SiO₂ · nH₂O

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Opal var. White Opal

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Formula: SiO₂

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Quartz var. Chalcedony

Formula: SiO₂

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ Quartz var. Quartzine

Formula: SiO₂

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

ⓘ 'Smectite Group'

Formula: A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O

References:

Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 4 - Oxides and Hydroxides
ⓘ	Goethite	4.00.	Fe³⁺O(OH)
ⓘ	Hematite	4.CB.05	Fe₂O₃
ⓘ	Quartz var. Chalcedony	4.DA.05	SiO₂
ⓘ		4.DA.05	SiO₂
ⓘ	var. Quartzine	4.DA.05	SiO₂
ⓘ	Opal	4.DA.10	SiO₂ · nH₂O
ⓘ	var. Lussatite	4.DA.10	SiO₂ · nH₂O
ⓘ	var. Opal Matrix	4.DA.10	SiO₂ · nH₂O
ⓘ	var. White Opal	4.DA.10	SiO₂ · nH₂O
ⓘ	var. Opal-CT	4.DA.10	SiO₂ · nH₂O
ⓘ	var. Opal-C	4.DA.10	SiO₂ · nH₂O
ⓘ	Anatase	4.DD.05	TiO₂
Group 5 - Nitrates and Carbonates
ⓘ	Calcite	5.AB.05	CaCO₃
Group 7 - Sulphates, Chromates, Molybdates and Tungstates
ⓘ	Gypsum	7.CD.40	CaSO₄ · 2H₂O
Group 9 - Silicates
ⓘ	Muscovite var. Illite	9.EC.15	K_0.65Al_2.0[Al_0.65Si_3.35O₁₀](OH)₂
ⓘ		9.EC.15	KAl₂(AlSi₃O₁₀)(OH)₂
ⓘ	Kaolinite	9.ED.05	Al₂(Si₂O₅)(OH)₄
Unclassified
ⓘ	'Opalite'	-
ⓘ	'Leucoxene'	-
ⓘ	'Smectite Group'	-	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O

List of minerals for each chemical element

H	Hydrogen
H	ⓘ Goethite	Fe³⁺O(OH)
H	ⓘ Gypsum	CaSO₄ · 2H₂O
H	ⓘ Muscovite var. Illite	K_0.65Al_2.0[Al_0.65Si_3.35O₁₀](OH)₂
H	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
H	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
H	ⓘ Opal	SiO₂ · nH₂O
H	ⓘ Opal var. Lussatite	SiO₂ · nH₂O
H	ⓘ Opal var. Opal Matrix	SiO₂ · nH₂O
H	ⓘ Smectite Group	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O
H	ⓘ Opal var. Opal-CT	SiO₂ · nH₂O
H	ⓘ Opal var. Opal-C	SiO₂ · nH₂O
C	Carbon
C	ⓘ Calcite	CaCO₃
O	Oxygen
O	ⓘ Anatase	TiO₂
O	ⓘ Calcite	CaCO₃
O	ⓘ Quartz var. Chalcedony	SiO₂
O	ⓘ Goethite	Fe³⁺O(OH)
O	ⓘ Gypsum	CaSO₄ · 2H₂O
O	ⓘ Hematite	Fe₂O₃
O	ⓘ Muscovite var. Illite	K_0.65Al_2.0[Al_0.65Si_3.35O₁₀](OH)₂
O	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
O	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
O	ⓘ Opal	SiO₂ · nH₂O
O	ⓘ Quartz	SiO₂
O	ⓘ Quartz var. Quartzine	SiO₂
O	ⓘ Opal var. Lussatite	SiO₂ · nH₂O
O	ⓘ Opal var. Opal Matrix	SiO₂ · nH₂O
O	ⓘ Smectite Group	A_0.3D_2-3[T₄O₁₀]Z₂ · nH₂O
O	ⓘ Opal var. Opal-CT	SiO₂ · nH₂O
O	ⓘ Opal var. Opal-C	SiO₂ · nH₂O
Al	Aluminium
Al	ⓘ Muscovite var. Illite	K_0.65Al_2.0[Al_0.65Si_3.35O₁₀](OH)₂
Al	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
Al	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
Si	Silicon
Si	ⓘ Quartz var. Chalcedony	SiO₂
Si	ⓘ Muscovite var. Illite	K_0.65Al_2.0[Al_0.65Si_3.35O₁₀](OH)₂
Si	ⓘ Kaolinite	Al₂(Si₂O₅)(OH)₄
Si	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
Si	ⓘ Opal	SiO₂ · nH₂O
Si	ⓘ Quartz	SiO₂
Si	ⓘ Quartz var. Quartzine	SiO₂
Si	ⓘ Opal var. Lussatite	SiO₂ · nH₂O
Si	ⓘ Opal var. Opal Matrix	SiO₂ · nH₂O
Si	ⓘ Opal var. Opal-CT	SiO₂ · nH₂O
Si	ⓘ Opal var. Opal-C	SiO₂ · nH₂O
S	Sulfur
S	ⓘ Gypsum	CaSO₄ · 2H₂O
K	Potassium
K	ⓘ Muscovite var. Illite	K_0.65Al_2.0[Al_0.65Si_3.35O₁₀](OH)₂
K	ⓘ Muscovite	KAl₂(AlSi₃O₁₀)(OH)₂
Ca	Calcium
Ca	ⓘ Calcite	CaCO₃
Ca	ⓘ Gypsum	CaSO₄ · 2H₂O
Ti	Titanium
Ti	ⓘ Anatase	TiO₂
Fe	Iron
Fe	ⓘ Goethite	Fe³⁺O(OH)
Fe	ⓘ Hematite	Fe₂O₃

Other Regions, Features and Areas containing this locality

Australia

Adelaide SuperbasinBasin
Arrowie BasinBasin
Delamerian OrogenOrogen
Eromanga BasinBasin
South Australia
- Central North
- Gawler CratonCraton
  - Olympic DomainCraton
- Lake Eyre Basin
  - Billa Kalina BasinBasin

Australian PlateTectonic Plate

This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.

References

Barnes, L. C., & Scott, D. C. (1979). Opal at Stuart Creek, Charlie Swamp and Yarra Wurta Cliff (No. 1). report.

[1]Thiry, M., & Milnes, A. R. (1991). Pedogenic and groundwater silcretes at Stuart Creek opal field, South Australia. Journal of Sedimentary Research, 61(1).

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