Name: Garden Well mine.

Location: The mine deposit is located 100 km north of Laverton, in the Duketon greenstone belt, in Western Australia.

Mine Owner/s: Regis Resources.

Brief Description: Garden Well is the biggest and most recent gold discovery in the Duketon area. The operation currently has a five-year mine life.

Brief History: There are no historical gold workings or previous drilling associated with the deposit, making Garden Well a blind virgin discovery.

The Garden Well area was first drilled in late 2008 using reconnaissance aircore drilling, targeting an area with surficial cover along strike of the concealed Moolart Well deposit discovered in 2001. In early 2010, further aircore, reverse circulation and diamond drilling started on a 40 m x 40 m grid; a maiden reserve was announced in December 2010. Following a revised reserve study in March 2011, a definitive feasibility sudy was completed in June 2011. 

Construction of a new  gold plant and a  250-man village started in August 2011 and was completed on time in the September 2012 quarter at a cost of $113-million. 

Primary Metals/Minerals: Gold.

Secondary Metals/Minerals: None stated.

Geology/Mineralisation: Garden Well is a shear hosted Archaean orogenic gold deposit.

The deposit is covered by a Tertiary palaeochannel up to 30 m thick and has no surface geochemical response, but does display moderate gold anomalies on the margins of the palaeochannel distal from the deposit. Moderate eight parts per billion (ppb) to 75 ppb gold anomalies on the palaeochannel margin were tested using the 2008 aircore drilling, and may represent gold leakage anomalies at the base of the palaeochannel or a truncated surface gold anomaly.

Gold mineralisation occurs as oxide ore down to 70 m below the base of the palaeochannel, and hypogene ore was drilled to a depth of 400 m. Gold mineralisation is open at depth. Oxide mineralisation comprises a 70-m- to 100-m-wide moderate east-dipping gold-bearing zone in clay-rich residual Archaean saprolite, with some subhorizontal supergene gold developed in the upper part of the saprolite profile. Host rocks are strongly sheared, moderately east-dipping Archaean ultramafic rocks in contact with overlying moderately east-dipping argillaceous sediments. The shear zone continues as primary hypogene mineralisation below the top of fresh rock and is characterised by a 50-m- to 70-m-wide strongly altered quartz-dolomite-fuchsite-chlorite-pyrite zone in ultramafic rocks. 

Reserves: Total proven and probable reserves as at March 31, 2020, were estimated at 17-million tonnes grading 0.9 g/t gold.

Resources: Total measured, indicated and inferred resources as at March 31, 2020, were estimated at 67-million tonnes grading 0.7 g/t gold.

Mining Method: Openpit. Mining is conducted using truck-and-shovel excavation methods by Mining and Civil Australia.

Major Infrastructure and Equipment: The gold plant design is based on a nominal four-million-tonne-a-year throughput, using a three-stage crushing circuit, a scrubber and a single ball mill followed by gravity and carbon-in-leach circuits.

The mine includes a 250-person village.

Prospects: Regis Resources is investigating the feasibility of an underground mine at Garden Well.

Contact Details:
Regis Resources
Tel +61 8 9442 2200
Email enquiries@regisresources.com
Website https://regisresources.com.au