Silver City Minerals Limited (ASX: SCI) announced that high-grade rock assay results up to 1,109 g/t gold (35 oz/t) were returned from 3 priority prospects within the company’s Austin gold project in Western Australia. The company said that the rock assay results indicate that all three prospects will be high-priority drill targets for Silver City.
Silver City said that due to the coarse nature of the gold observed in the field across the project, it had commenced an assessment of the LeachWELL gold assay technique. The company said that the recent results show the LeachWELL analysis show a significant increase in grade in the range of 4.6-53.4% compared to conventional fire assay techniques.
The company said that a total of 13 RC samples from a drill program in 2020 by the Vendor were also taken for the LeachWELL assay technique with results expected to be released shortly.
SCI said that a review of the detailed airborne magnetic data as well as historic geochemistry is also currently underway.
Austin gold project
The company had recently acquired an 80% stake in the Austin Gold Project. The Austin Project is a highly prospective opportunity for Silver City with abundant gold at surface.
The limited shallow drilling undertaken had returned a number of high-grade intersections including 6 m at 15.8 g/t Au from 36m (including 2 m at 43 g/t Au) in BGRC-03 at the Brunswick Hill prospect. Several significant historic gold intersections and highly mineralized outcrops were never properly followed up.
Significant prospects within the Austin gold project include Brians, Teds Gardners, Mt Sandy, Lady Zena, Buccaneer SE, Teds Akos, Teds Main, Shadow, Brunswick Hill, Teds SW, Four Shafts, Old Granites (east), and Buccaneer/Mitchell Flats.
High-grade rock sample results
Silver City geologists had conducted a field trip during the dates of 27th to 29th January 2021 as part of the due diligence on the Austin gold project. The company said that assay results were received and reviewed for a total of 29 rock samples taken from several prospect areas across the project.
SCI said that high-grade rock assay results from the Austin Gold Project were returned from 3 priority prospects including: up to 1,109 g/t gold (35 oz/t) from the Brians prospect in outcropping northwest trending veins that occur in a similar orientation to the mineralisation at the nearby Starlight, White Light and White Heat discoveries by Musgrave Minerals (ASX: MGV); up to 57.1 g/t gold (1.8 oz/t) from the Teds prospect area from a small costean where the abundant and spectacular coarse gold has been previously observed associated with weathered quartz veins; and up to 10.2 g/t gold at the Mt Sandy prospect area from a quartz vein exposed near a historic mine adit.
The company said that the rock assay results are extremely encouraging for the project and indicate that all three prospects will be high priority drill targets for Silver City.
Significant assay results from various prospects are as shown below.
SCI said that the assays were detected using the LeachWELL gold assay technique, chosen because of the course nature of mineralisation detected in the field.
LeachWELL analysis
Due to the coarse nature of the gold observed in the field across the project, Silver City had commenced an assessment of the LeachWELL gold assay technique.
The LeachWELL technique assays a much larger split of the pulverised sample, either 500 g or 1 kg versus a 50 gram split for the conventional fire assay technique. The LeachWELL technique is designed to give a better representative assay sample on projects and deposits that display unusually coarse nuggetty gold.
The company said that the LeachWELL analysis upgraded the gold assays significantly, in some cases over 50%. SCI said that this work suggests that LeachWELL analysis will be an important assay technique for upcoming drill programs on the project in order to get a representative gold assay to overcome the coarse nature of the gold observed across the project.
Latest updates
Silver City announced that following work programs are currently underway on the Austin Gold Project to assist the drill targeting work.
13 RC samples for LeachWELL technique
The company said that a total of 13 RC samples from a drill program in 2020 by the Vendor were also taken for the same LeachWELL assay techniques adopted for the rock samples. SCI said that the results are currently being reviewed and will be reported in the coming weeks.
Regolith mapping
The company said that Regolith mapping is currently underway that utilises high-resolution satellite Sentinel imagery to incorporate into the reprocessing, relevelling, and interpretation of the historic soil geochemistry data from the 15 km trend from Lady Zena to Mt Brunswick to identify subtle gold-in-soil anomalies.
Other work programs
SCI said that the reprocessing of airborne magnetic data specifically to target and interpret cross structures particularly those on a northeast orientation that are known to hoist high grade gold in the district is now underway. The company said that the digitisation of all historic drill data into a comprehensive database is also ongoing.
What’s next?
Silver City reported that the work programmes that will be planned in the coming months include a gradient array IP survey to cover the area from Mt Brunswick to Brians in order to identify areas of extensive disseminated sulphide and silicification/quartz veining associated with gold mineralisation; completion of a targeting matrix across the project to rank each of the targets across the Austin Gold Project; and preliminary maiden drill program at the Brunswick Hill and Brians prospects where highly mineralised gold intersections have never been followed up at depth.
SCI said that in addition to RC drilling, it also plans to complete strategic diamond drill holes to accurately define the orientation of gold-bearing veins and sulphide alteration.
Image Source: Silver City Minerals Limited