Operations

Following the announcements of encouraging drilling results at Blanket Mine on July 10, 2023 and January 30, 2024, Caledonia was able to announce an increase to the mineral resources and mineral reserves estimates at Blanket.

Highlights

• Increase in Blanket’s 1300 S-K mineral reserve and mineral resource ounces by 111% and 36% respectively, with a 7% and 23% increase in mineral reserve and mineral resource grade respectively.
• Increase in Blanket’s NI 43-101 mineral reserve and measured and indicated (“M&I”) mineral resource ounces by 106% and 63% respectively, with a 5% and 14% increase in mineral reserve and M&I mineral resource grade
• Increase in Blanket’s NI 43-101 inferred mineral resource ounces by 26% with an increase in inferred mineral resource grade of 28%.
• Blanket’s life of mine is estimated, based only on the updated mineral reserves estimate, to 2034. Management believes that the inferred mineral resources may, based on past successful conversion rates, further extend the life of mine past 2040.
• Release of 1300 S-K mineral reserves and resources estimates at the Bilboes Gold Project (“Bilboes”) for the first time, which, using the same methodology, are similar to current NI 43-101 mineral reserves and mineral resources estimates.

Further details

The total 1300 S-K M&I mineral resource estimate at Blanket, exclusive of mineral reserves and at 64% attributable ownership to Caledonia (as reported pursuant to 1300 S-K), has increased by 50% to 606k ounces of gold in 5,426k tonnes with a 16% improvement in grade and the total mineral reserves estimate at Blanket has increased by 111% to 519k ounces of gold in 4,918k tonnes with a 7% improvement in grade. The moderate increase in inferred mineral resource, by 26% to 679k ounces of gold in 5,646k tonnes, is due to successfully converting the bulk of the inferred mineral resources into indicated mineral resources as evidenced by the 2% drop in tonnes and is offset by a 28% increase in grade.

A comparison of the 1300 S-K measured, indicated and inferred mineral resources estimates as at December 31, 2022 with those as at December 31, 2023 at Blanket are shown below:

Notes: 

1. Cut-off applied 1.5 g/t.
2. 2022 – No geological loss applied for measured, 5% for indicated and inferred.
3. 2023 – Geological loss for measured 2.5%, indicated 5%, inferred 10%.
4. 2022 – Commodity price of $1,800/oz.
5. 2023 – Commodity price of $2,150/oz.
6. Mineral resources are reported as 64% attributable to Caledonia. 
7. All orebodies are depleted for mining.
8. Mineral resources are stated exclusive of mineral reserves.
9. Plant recovery factor of 93.64% applied.

A comparison of the 1300 S-K mineral reserves estimates as at December 31, 2022 with those as at December 31, 2023 at Blanket are shown below:

Notes (December 31,2023):

1. Mineral reserve cut-off of 2.1 g/t applied.
2. The gold price that has been utilised in the economic analysis to convert diluted measured and indicated mineral resources in the life or mine (“LoM”) plan to mineral reserves is an average real term price of USD1,877/oz over the LoM, using the forecast prices as per economic analysis.
3. The mineral reserve estimation utilises the depleted 2023 mineral resource estimation and the 2023 mine design and LoM plan.
4. Mineral reserves are reported as 64% attributable to Caledonia.
5. Totals may not add due to rounding.

The total NI 43-101 M&I mineral resource estimates at Blanket, inclusive of mineral reserves (as reported in the New Blanket NI 43-101), have increased from the estimates set out in the technical report entitled “NI 43-101 Technical Report on the Blanket Gold Mine, Zimbabwe” dated March 13, 2023 prepared by Caledonia and Minxcon (Pty) Ltd and filed on SEDAR (www.sedar.com) on March 13, 2023 (“Previous Blanket NI 43-101”), by 63% to 1,789k ounces of gold in 15,273k tonnes and the total mineral reserves estimates at Blanket have increased by 106% to 812k ounces of gold in 7,684k tonnes. Again, the moderate increase in inferred mineral resources, by 26% to 1,061k ounces of gold in 8,821k tonnes, is due to successfully converting the bulk of the inferred mineral resources into indicated mineral resources as evidenced by the 2% drop in tonnes and is offset by a 28% increase in grade.

The following table shows a comparison of the new measured, indicated and inferred mineral resources estimates under the New Blanket NI 43-101 with those set out in the Previous Blanket NI 43-101:

Mineral resources (December 31, 2023)

Notes:

1. Cut-off applied 1.5 g/t.
2. Geological loss applied: measured 2.5%, indicated 5.0%, inferred 10.0%.
3. Commodity price utilised: USD2,150/oz.
4. Mineral resources are stated inclusive of mineral reserves.
5. Mineral resources are reported as total mineral resources and are not attributed.
6. All orebodies are depleted for mining.
7. Totals may not add due to rounding.

The following table shows a comparison of the new mineral reserves estimates under the New Blanket NI 43-101 with those set out in the Previous Blanket NI 43-101:

.

Mineral reserves (March 1, 2024)

Notes:

1. Mineral reserve cut-off of 2.1 g/t applied.
2. The gold price that has been utilised in the economic analysis to convert diluted measured and indicated mineral resources in the LoM plan to mineral reserves is an average real term price of USD1,877/oz over the LoM.
3. Mineral reserves are reported as total mineral reserves and are not attributed.
4. Totals may not add due to rounding.

The tables below compare the mineral resources and mineral reserves estimates in the Bilboes NI 43-101 Report as at December 15, 2021 to the 1300 S-K mineral resources and reserves estimates for Bilboes in the Annual Report which are stated with an effective date of December 31, 2023.  Column B in the table below shows the 1300 S-K mineral resources, but inclusive of mineral reserves so as to more easily show the correlation with the NI 43-101 Bilboes Report mineral resources.  The final table shows a comparison of the mineral reserves.

Full details of drilling results can be seen in the press releases announced on

30 January 2024
https://polaris.brighterir.com/public/caledonia_mining/news/rns_tool/story/r7l2nvx

and 10 July 2023
https://polaris.brighterir.com/public/caledonia_mining/news/rns_tool/story/w3j603x