Project Background:
The Yuinmery Calcrete Deposit is located 570 km north-east of Perth, WA, 140 kilometres north-east of Paynes Find. It is located on Exploration Licence 57/1185 and partially covered by the historical mining tenement M57/245, which is approximately 10 kilometres east of the Yuinmery Homestead and 30 kilometres east of the Youanmi Gold Mine, which is advancing towards a restart of mining and processing activities. Venus through its wholly owned subsidiary Redscope Enterprises Pty Ltd (“Redscope”), has identified a calcrete resource at Yuinmery located on a portion of exploration licence 57/1185 (“E57/1185”) (Figure 1) over which it has the rights to explore for, and if warranted, mine calcrete under a split commodity arrangement with the tenement holder. At the request of Redscope, the tenement holder has applied for a mining lease M57/672 (which covers all of cancelled Mining Lease M57/245) and over the additional area upon which the calcrete resource has been identified, and upon grant, Redscope or nominee has the exclusive right to carry out further feasibility work and to mine the calcrete resource.
Figure 1: Yuinmery Calcrete Deposit Location
Widenbar & Associates Pty Ltd (“Widenbar”) was commissioned to produce a JORC 2012 compliant Mineral Resource Estimate (“MRE”) for the Yuinmery Calcrete Deposit (refer ASX announcement 20 Dec 24).
The Mineral Resource has been classified in the Measured and Indicated categories, in accordance with the 2012 Australasian Code for Reporting of Mineral Resources and Ore Reserves (JORC Code). The current resource estimate is summarised below.
Table 1. Total Resource Estimate
* Acid neutralising capacity (Widenbar Associates, December 2024)
Geology:
The tenement (M57/245) covers part of a calcrete deposit within an ephemeral drainage delta on the western end of Lake Noondie. The creek system drains 50 kilometres of strike of the Youanmi Fault and the southwest end of the Sandstone Greenstone Belt around Bellchambers. This creek system ponds in the Rays Rock area and has a summer standing water table of approximately four metres depth.
The overall calcrete horizon in the exploration tenement is generally five metres thick, being white to pink-brown in colour, with large variations in homogeneity and texture and with differing degrees of dissolution, recrystallisation and cementation. Within the calcrete horizon, secondary silicification is common between depths of three to five metres and gypsum is present between four and five metres depth. The area drilled by GMA and the subject of this MRE is more continuous and homogenous and the resource is limited to the top two metres of the calcrete horizon.
The calcrete material forms a continuous layer, which has been drilled on a nominal 10m grid to a depth of two meters. As such, there is no conventional geological interpretation, with the calcrete layer being defined by the area of drilling.
Historical Drilling and Sampling
Previous exploration and mining at M57/245 include the following:
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- Outcrop sampling was carried out between 1992 and 1993 (WAMEX report A38638)
- In 1993, 41 RAB holes were drilled at 25m x 25m and 50m x 50m spacing to a depth of 5m.
- This delineated an area of calcrete mineralisation in the general area of the current calcrete pit (WAMEX report A40445).
- A total of 1,059 two-metre blast holes were subsequently drilled in the area of the current calcrete pit. A total of 27,300 tonnes of calcrete was mined in 1996 and 1997 and transported to the Youanmi Gold Mine as a substitute for the use of lime for acid neutralisation in the gold extraction process (WAMEX reports A47611 & A51311).
- A total of 27,300 tonnes of calcrete was mined in 1996 and 1997 and transported to the Youanmi Gold Mine as a substitute for the use of lime for acid neutralisation in the gold extraction process (WAMEX reports A47611 & A51311).
Drilling in the north-eastern corner of M57/245 approximately 500m from the existing pit was carried out in 1997 by Gold Mines of Australia (“GMA”); 448 RAB holes were drilled (to 2m depth), with 376 samples tested for acid neutralising capacity (Wamex report A51311). The drill samples collected by GMA for analysis of the lime content were of approximately one kilogram over a two metre drill interval and were submitted to the Youanmi Gold Mine laboratory for testing of their acid neutralising capacity.
Sample preparation had a 250g portion of each sample crushed and pulverised. A two gram sample was sub split and weighed, then added to 50 ml of water with the pH being measured. The pH was adjusted to approximately 5.0 by titration with 10% HCl. The volume of acid solution titrated and the final pH were recorded. An acid volume of at least 4 ml is considered adequate for use in the Youanmi mill (standard quicklime response is between 10 and 11.2).
Figure 2. Drill Hole Locations and historical ML 57/245
Resource Model Estimation
An “empty” rock model was created using the topographic as a constraint. Block model parameters are summarised below.
Table 2. Block Model Parameters
Figure 3. Block Model Acid Concentration vs Data
Comparison of Data and Model
Resource Classification
The Mineral Resource has been classified in the Measured and Indicated categories, in accordance with the 2012 Australasian Code for Reporting of Mineral Resources and Ore Reserves (JORC Code).
Figure 4. Resource Classification
The current resource estimate is shown below for the total resource and the portion within M 57/245.
Table 3. Total Resource Estimate Summary
Table 4. Resource Estimate within Historical M 57/245 Licence 
(please refer JORC 2012 compliant Mineral Resource Estimate in ASX announcement 20 Dec 2024)