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Lass O'Gowrie Gold Mine, Mount Monger, Mount Monger Goldfield, Kalgoorlie-Boulder Shire, Western Australia, Australiai
Regional Level Types
Lass O'Gowrie Gold MineMine
Mount MongerMountain
Mount Monger GoldfieldOre Field
Kalgoorlie-Boulder ShireShire
Western AustraliaState
AustraliaCountry

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Latitude & Longitude (WGS84):
31° 2' 30'' South , 121° 56' 36'' East
Latitude & Longitude (decimal):
Type:
Nearest Settlements:
PlacePopulationDistance
Stoneville2,841 (2016)25.7km
Boulder5,178 (2017)51.9km
Williamstown161 (2018)54.6km
Kalgoorlie31,107 (2014)55.5km
Mindat Locality ID:
271728
Long-form identifier:
mindat:1:2:271728:2
GUID (UUID V4):
0


The Lass O'Gowrie was discovered by a prospector called McLellan (surname) in 1920. It was shortly after sold to John Stevenson, Bedford and Melvin, who named it Lass O'Gowrie. Again very shortly after a company called the Lass O'Gowrie Gold Mining Company was formed in Adelaide with 250 000 pounds capital. GML 4803E and 4835E. 48 acres.

It was a debacle from the start. The mine was severely over capitalised. No independent investigation of the deposit was carried out before the company took over. Questions were raised where the money was going. A little over 13 000 pounds was paid to the vendors for a twelve month working option, a huge amount for the time.

Not all were critical. The Kalgoorlie Mayor arranged a largely attended public protest meeting over unfavourable reports about the Mount Monger Goldfield in Perth and Eastern States newspapers.

The company sank six shafts to varying depths on a very broken green
chloritic schist, with talc on the walls, carrying very fine gold.

The company appointed one of the vendors as the mine manager. As a result they received glowing reports about developments at head office in Adelaide. Government geologists were refused permission to inspect the mine.

At the end of the twelve month option they sought a further extension of the option, which the vendors agreed to for 2000 pounds. In this period the company appointed former mine manager, J.H. Harris to inspect the mine. He found very little gold. The vendors challenged the accuracy of the report. So the company appointed mine manager A.W. Martin to report on the mine. He found even less gold than Harris.

This was not initially communicated to the shareholders until a meeting recommending liquidation of the company in April 1921. It came to light at the meeting, the majority of the shareholder's funds had been invested in the share market by an incompetent financial officer, and all the money had been lost.

In 1924, it is reported a party of prospectors had sunk a new shaft to 100 feet, south of the old workings. The prospectors had extracted 28.5 tonnes of ore for 29.5 ounces of gold. This had been obtained by ancient methods of a windlass and bucket, and took several months. The report notes the mine is unpayable. Campbell and Houston (surnames) are names mentioned.

Sam Thompson, Arthur Smith, and McCahon take over in 1925, and produce some small crushings.

Pegging new leases had involved waiting outside the Mining Register's office in Kalgoorlie, for notices of abandoned leases to be posted. There was then sometimes a rush out to the goldfield to peg it. Matthias Dunne decided to use a different method in 1937. He was camped in the area, and when the notice was posted he had someone send him a wireless message. Within ten minutes he had pegged the lease. Other prospectors arrived from Kalgoorlie later in the day, and pegged over the lease. Dunne was successful in obtaining ownership later in the Warden's court.

Lass O'Gowrie is at the south-eastern end on the line of workings at Mount Monger. It is located approximately 500 metres south-east of the Mirror open pit, as a collection of shafts, and shallow workings bordering either side of the track.

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


13 valid minerals.

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:

Anatase
Formula: TiO2
Antigorite
Formula: Mg3(Si2O5)(OH)4
Calcite
Formula: CaCO3
'Chlorite Group'
Clinochlore
Formula: Mg5Al(AlSi3O10)(OH)8
'Feldspar Group'
Magnesite
Formula: MgCO3
Magnesite var. Mesitine Spar
Formula: (Mg,Fe)CO3
Magnetite
Formula: Fe2+Fe3+2O4
Native Gold
Formula: Au
Quartz
Formula: SiO2
Rutile
Formula: TiO2
Schorl
Formula: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
Talc
Formula: Mg3Si4O10(OH)2
'Tourmaline'
Formula: AD3G6 (T6O18)(BO3)3X3Z
Tremolite
Formula: ◻Ca2Mg5(Si8O22)(OH)2
Zircon
Formula: Zr(SiO4)

Gallery:

List of minerals arranged by Strunz 10th Edition classification

Group 1 - Elements
Native Gold1.AA.05Au
Group 4 - Oxides and Hydroxides
Magnetite4.BB.05Fe2+Fe3+2O4
Quartz4.DA.05SiO2
Rutile4.DB.05TiO2
Anatase4.DD.05TiO2
Group 5 - Nitrates and Carbonates
Calcite5.AB.05CaCO3
Magnesite5.AB.05MgCO3
var. Mesitine Spar5.AB.05(Mg,Fe)CO3
Group 9 - Silicates
Zircon9.AD.30Zr(SiO4)
Schorl9.CK.05NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)
Tremolite9.DE.10◻Ca2Mg5(Si8O22)(OH)2
Talc9.EC.05Mg3Si4O10(OH)2
Clinochlore9.EC.55Mg5Al(AlSi3O10)(OH)8
Antigorite9.ED.15Mg3(Si2O5)(OH)4
Unclassified
'Chlorite Group'-
'Feldspar Group'-
'Tourmaline'-AD3G6 (T6O18)(BO3)3X3Z

List of minerals for each chemical element

HHydrogen
H AntigoriteMg3(Si2O5)(OH)4
H ClinochloreMg5Al(AlSi3O10)(OH)8
H SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
H TalcMg3Si4O10(OH)2
H Tremolite◻Ca2Mg5(Si8O22)(OH)2
BBoron
B SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
B TourmalineAD3G6 (T6O18)(BO3)3X3Z
CCarbon
C CalciteCaCO3
C MagnesiteMgCO3
C Magnesite var. Mesitine Spar(Mg,Fe)CO3
OOxygen
O AnataseTiO2
O AntigoriteMg3(Si2O5)(OH)4
O CalciteCaCO3
O ClinochloreMg5Al(AlSi3O10)(OH)8
O MagnesiteMgCO3
O MagnetiteFe2+Fe23+O4
O QuartzSiO2
O RutileTiO2
O SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
O TalcMg3Si4O10(OH)2
O TourmalineAD3G6 (T6O18)(BO3)3X3Z
O Tremolite◻Ca2Mg5(Si8O22)(OH)2
O ZirconZr(SiO4)
O Magnesite var. Mesitine Spar(Mg,Fe)CO3
NaSodium
Na SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
MgMagnesium
Mg AntigoriteMg3(Si2O5)(OH)4
Mg ClinochloreMg5Al(AlSi3O10)(OH)8
Mg MagnesiteMgCO3
Mg TalcMg3Si4O10(OH)2
Mg Tremolite◻Ca2Mg5(Si8O22)(OH)2
Mg Magnesite var. Mesitine Spar(Mg,Fe)CO3
AlAluminium
Al ClinochloreMg5Al(AlSi3O10)(OH)8
Al SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
SiSilicon
Si AntigoriteMg3(Si2O5)(OH)4
Si ClinochloreMg5Al(AlSi3O10)(OH)8
Si QuartzSiO2
Si SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Si TalcMg3Si4O10(OH)2
Si Tremolite◻Ca2Mg5(Si8O22)(OH)2
Si ZirconZr(SiO4)
CaCalcium
Ca CalciteCaCO3
Ca Tremolite◻Ca2Mg5(Si8O22)(OH)2
TiTitanium
Ti AnataseTiO2
Ti RutileTiO2
FeIron
Fe MagnetiteFe2+Fe23+O4
Fe SchorlNaFe32+Al6(Si6O18)(BO3)3(OH)3(OH)
Fe Magnesite var. Mesitine Spar(Mg,Fe)CO3
ZrZirconium
Zr ZirconZr(SiO4)
AuGold
Au Native GoldAu

Other Regions, Features and Areas containing this locality

Australia
Australian PlateTectonic Plate

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