Inventus Mining Announces Results from Bulk Sampling Program at Pardo Project

Inventus Mining Corp. (“Inventus” or the “Company”) is pleased to announce the results from its bulk sampling program at its 100%-owned Pardo Project near Sudbury, Ontario. The 5,000-tonne bulk sample from the 007 Zone returned an average head grade of 3.4 g/t gold (Au) with excellent gravity recoverable gold. The bulk sampling program was successful in reconciling the gold mineralization in the predictive block model that was generated using large diameter infill diamond drill holes.

Key results include:

• A total of 4,979 dry tonnes of mineralized rock was processed with a head grade of 3.4 g/t Au.
• Bulk sample head grade reconciled strongly with the predictive block model grade of 3.3 g/t Au.
• Gravity and flotation concentrate contained 438 oz Au, worth approximately Cad$1,000,000.
• Of the 438 oz Au recovered, 299 oz Au representing 68% was contained in the gravity concentrate, and 138 oz Au representing 32% was contained in the flotation concentrate.
• The overall metallurgical performance of the bulk sample did not balance, which is attributed to high gravity recoverable gold, and approximately 76 oz Au is estimated to remain in the mill circuit.

Geology and Mineralization

The 007 Zone bulk sample was extracted from a horizontal mineralized conglomerate “reef” that occurred from surface to a depth of 4 metres (m). The conglomerate reef was on average 2.5 m thick and consisted of 72% clasts and 28% matrix all the mineralization is contained in the matrix. The mineralization occurs as disseminated pyrite and gold within the matrix that surrounds the clasts within the conglomerate. The conglomerate reef had a sharp footwall contact that is easily identified during mining.

Infill Drilling and Block Model Prediction

Prior to extraction of the bulk sample, the area was diamond drilled with 28 large diameter (7 cm) holes at 5-m centers for grade estimation purposes. Samples of the drill core used in the predictive block model were subject to density measurements (2.79 t/m³) and whole-core sampling to provide an adequate sample size for assay. Geological contacts from the infill drilling were used to create hard boundaries for wireframing the block model domain. The predicted block model had 5,526 tonnes grading 3.3 g/t Au.

Mining and Grade Control

Bulk sample extraction was relatively simple due to the location on surface and horizontal orientation. The bulk sample was drilled and blasted at 1.2-metre centers, and mineralized material was crushed on site to under 4-inches. Due to winter weather conditions during mining, tight controls on blast contacts and pit mucking were not consistently maintained. Post-operation assessment of the bulk sample pit has indicated approximately 450 tonnes of material was left in the pit and over-blasting of the footwall resulted in some dilution.

The mined block mined was from surface to the lower lithological contact of the mineralized reef. Drilling results showed that the upper portion of the reef (surface to 1-1.5 m depth) was the highest grade, while the portion closest to the footwall contact was much lower grade. The decision to extract the whole unit provided important information; however, a more selective mining approach targeting grade could be used.

Processing

A total of 5,140 wet tonnes was trucked to the mill near in Timmins between January and February 2022, as measured by the mill truck scale. Processing of the bulk sample occurred in mid-February and produced gravity and flotation concentrates. The results of the bulk sample are presented in Table 1. During the bulk sample run, a total of 89 ball mill feed samples and 88 tails samples were collected to produce nine daily composite samples for assay. The composite samples from the ball mill feed returned an average grade of 3.38 g/t Au (the “head grade”) and samples of the tails returned an average grade of 0.17 g/t Au (the “tails grade”).

The sample was calculated to contain 541 oz Au and a total of 438 oz Au was recovered, representing an apparent reconciled head grade of 2.9 g/t Au and a metallurgical recovery of 81%. However, due to the high percentage of gold recovered by gravity and the large discrepancy between the contained and recovered gold ounces, it is assumed that significant gold remained in the milling circuit. An effort was made to clean out the mill circuit resulting in recovery of 13.7 oz Au, but many areas were not cleaned, including the two ball mills. The amount of gold remaining in the mill circuit is estimated to be approximately 76 oz but cannot be measured. Therefore, the overall true reconciled head grade and recovery of the bulk sample is inconclusive.

Table 1. 007 Zone Bulk Sample Results

¹The estimated Au remaining in-circuit is the assumed amount of gold that was not recovered in the milling circuit. We believe that an in-circuit loss is very likely with high gravity recoverable gold and should be considered during future bulk sampling.

Concentrates

The gravity concentrates and high-grade mill cleanup material totalled 8.3 dry tonnes of material with an average grade of 1,118.4 g/t Au. The gravity concentrate was shipped to a smelter in Chicago where analysis showed 299.3 oz Au was contained. The flotation concentrate totalled 102.4 dry tonnes of material with an average grade of 42.0 g/t Au. The flotation concentrate was shipped to a smelter in Quebec where analysis showed 138.3 oz Au was contained.

Source: http://www.inventusmining.com/