Endeavor Mine (Elura Mine), Cobar, Robinson Co., New South Wales, Australiai

Regional Level Types
Endeavor Mine (Elura Mine)	Mine
Cobar	Mining District
Robinson Co.	County
New South Wales	State
Australia	Country

A silver-lead-zinc-copper deposit discovered in 1974 was originally worked as the Elura mine but presently (2005) is worked as the Endeavor mine.
Located in Booroondarra Parish near Cobar.

Coordinates: 371700mE, 6551350mN.
A lenticular massive sulphide deposit.

The Endeavor zinc-lead-silver mine is located 43km NNW of Cobar. The mine contains two styles of mineralisation: above about 900m depth an irregular sub-vertical sheet is hosted by a turbidite sequence and broadly coincides with an anticline axial plane; at the bottom of this sheet mineralisation bifurcates into grossly concordant zones. These concordant zones are hosted by a shale-rich sequence and underlying limestone.

The Electrolytic Zinc Company of Australasia Ltd discovered the orebody in 1973. Initially a bullseye anomaly was identified in an aeromagnetic survey, with diamond drilling intersecting ore in 1974 (Schmidt 1989). Mine production from what was initially known as the Elura orebody began in 1983. In 1998 drilling beneath the mine at over 1000m below the surface intersected mineralisation close to the contact with limestone, which until that time, was not recognised as occurring in the mine area.

CBH Resources Ltd, purchased the mine in 2003 and Production ramped up to 1.4MT per annum. At June 2005 the Endeavor Mine Resources totalled 17.7MT at 4.9%Pb, 8.7%Zn and 69g/tAg and Reserves 11MT at 4.5%Pb, 7.9%Zn and 66g/tAg. Mine production totals about 24MT.

The Endeavor mineralisation is contained within the Cobar Basin, which is in turn part of the Lachlan Fold Belt. Basement rocks include Ordovician sediments and Silurian granitic rocks. The basin contains mainly siliciclastic sediments with minor volcanic rocks and carbonates. Sedimentation continued from the Late Silurian until the Early Devonian. Polymetallic mineralisation within the Cobar Basin is thought to have coincided with a period of basin compression and folding (Lawrie and Hinman 1998). The mineralisation is largely discordant and vein or replacement in form. It is associated with silicic, carbonate and chlorite alteration. Most of the major known mineral deposits, including Endeavor, CSA, Peak and Hera are located along a linear structural corridor at least 200km in length. All of these major deposits are located adjacent to protrusions of basement into the Cobar Basin associated with gravity low anomalies. Most mineralisation is hosted by siliclastic marine turbidites.

High-grade massive sulphide mineralisation at Endeavor is enveloped by sulphide stringers, which are in turn enveloped by siderite alteration. The halo of siderite alteration extends for several tens of metres away from sulphide mineralisation and consists of 1 to 2mm diameter clots that replace sandy beds. Chloritic alteration also occurs.

Above about 900m depth the sulphide stringers form a large continuous lens or sheet which lies in an anticline axial plane. This lens ranges in thickness from 15 to 120m, extends from the surface to 900m at the S end of the mine, and has a strike length of at least 800m. At about 900m depth the mineralisation bifurcates into grossly concordant zones that dip down both the anticline limbs. The body of low-grade sulphides is open along strike in both directions and down dip on both limbs. Sulphide minerals form two textures within the stringer zone. Stringers of sulphide generally sub-parallel slaty cleavage in the axial plane zone. The stringers are 5mm to 2m thick and mainly consist of pyrite, sphalerite, galena and chalcopyrite. Siliceous alteration sometimes accompanies the sulphide stringers, particularly in the upper parts of the mine. Similar stringers parallel to cleavage also occur in the concordant zones. However, in addition pyrite and base metal sulphides form conformable sulphide blebs that generally replace sandstone/siltstone beds and laminae. These blebs are distributed close to the cleavage-parallel stringers.

Other Regions, Features and Areas containing this locality

References