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Reviewed Results | Year ended 31 December 2021

Review of Operations Review of operations

Year ended December 2021 compared with year ended December 2020

Figures may not add as they are rounded independently.

South Africa region

South Deep

    Dec 2021 Sept 2021 % Variance
   
Ore mined 000 tonnes 375 419 (11)%
Waste mined 000 tonnes 53 60 (12)%
Total tonnes 000 tonnes 428 479 (11)%
Grade mined – underground reef g/t 6.66 6.73 (1)%
Grade mined – underground total g/t 5.83 5.88 (1)%
Gold mined kg 2,499 2,820 (11)%
000'oz 80.3 90.7 (11)%
Destress m2 9,494 11,732 (19)%
Development m 1,447 1,640 (12)%
Secondary support m 3,814 4,343 (12)%
Backfill m3 93,949 83,475 13 %
Ore milled – underground reef 000 tonnes 354 430 (18)%
Ore milled – underground waste 000 tonnes 53 45 18 %
Ore milled – surface 00 0tonnes 288 280 3 %
Total tonnes milled 000 tonnes 695 755 (8)%
Yield underground reef g/t 6.65 6.30 6 %
Surface yield g/t 0.11 0.13 (15)%
Total yield g/t 3.44 3.63 (5)%
Gold produced kg 2,387 2,744 (13)%
000'oz 76.8 88.2 (13)%
Gold sold kg 2,387 2,847 (16)%
000'oz 76.8 91.5 (16)%
AISC R/kg 691,362 542,660 27 %
US$/oz 1,401 1,155 21 %
AIC R/kg 730,076 567,550 29 %
US$/oz 1,479 1,208 22 %
Sustaining capital expenditure Rm 468.1 260.9 79 %
US$m 31.1 17.9 74 %
Non-sustaining capital expenditure Rm 92.4 70.9 30 %
US$m 6.0 4.8 25 %
Total capital expenditure Rm 560.5 331.8 69 %
US$m 37.1 22.7 63 %

As previously guided, gold production decreased by 13% to 2,387kg (76,800oz) in the December quarter from 2,744kg (88,200oz) in the September quarter as a result of lower volumes mined due to fewer shifts worked as a result of the planned maintenance shutdown in the December month as well as the Christmas break. Critical maintenance work was carried out on the main shaft infrastructure limiting hoisting capacity. Total tonnes mined and gold mined were impacted by the same reasons and decreased by 11% to 428kt in the December quarter from 479kt in the September quarter and by 11% to 2,499kg (80,300oz) in the December quarter from 2,820kg (90,700oz) in the September quarter, respectively.

Reef yield increased by 6% to 6.65g/t in the December quarter from 6.30g/t in the September quarter due to an increase in broken reef grade mainly as a result of higher grades in destress area and improved underground recoveries.

Total underground tonnes milled decreased by 14% to 407kt in the December quarter from 475kt in the September quarter in line with the decrease in total tonnes broken, mined and hoisted. Surface tonnes milled increased by 3% to 288kt in the December quarter from 280kt in the September quarter as treatment of surface tonnes was temporally slowed down in September quarter due to cyanide shortages.

Development decreased by 12% to 1,447 metres in the December quarter from 1,640 metres in the September quarter and similarly destress decreased by 19% to 9,494m2 in the December quarter from 11,732m2 in the September quarter as fewer shifts were worked in the December quarter due to the maintenance shutdown and the Christmas break.

Secondary support installed decreased by 12% to 3,814 metres in the December quarter from 4,343 metres in the September quarter, which is in line with reduced development and destress performance. Backfill increased by 13% to 93,949m3 in the December quarter from 83,475m3 in the September quarter due to the increase in number of stopes available for backfilling

All-in cost increased by 29% to R730,076/kg (US$1,479/oz) in the December quarter from R567,550/kg (US$1,208/oz) in the September quarter mainly due to a decrease in gold sold and an increase in capital expenditure (solar plant and equipment deliveries), partially offset by the decrease in operational expenditure compared to the September quarter.

Total capital expenditure increased by 69% to R561m (US$37m) in the December quarter from R332m (US$23m) in the September quarter.

Sustaining capital expenditure increased by 79% to R468m (US$31m) in the December quarter from R261m (US$18m) in the September quarter mainly due to the delivery of equipment, solar plant expenditure, Doornpoort tailings storage facility expansion and underground mobile equipment delivered in the December quarter.

Non-sustaining capital expenditure increased by 30% to R92m (US$6m) in the December quarter from R71m (US$5m) in the September quarter due to an increase in new mine infrastructure projects (conveyors, crushers, and backfill pipe installations).

West Africa region

Ghana

Tarkwa

    Dec 2021 Sept 2021 % Variance
   
Ore mined 000 tonnes 3,545 3,034 17 %
Waste (Capital) 000 tonnes 9,504 15,361 (38)%
Waste (Operational) 000 tonnes 8,111 5,736 41 %
Total waste mined 000 tonnes 17,615 21,097 (17)%
Total tonnes mined 000 tonnes 21,160 24,131 (12)%
Strip ratio waste/ore 5.0 7.0 (29)%
Grade mined g/t 1.31 1.36 (4)%
Gold mined 000'oz 149.8 132.9 13 %
Tonnes milled 000 tonnes 3,401 3,493 (3)%
Yield g/t 1.18 1.21 (2)%
Gold produced 000'oz 129.1 135.7 (5)%
Gold sold 000'oz 129.1 135.7 (5)%
AISC US$/oz 1,127 1,091 3 %
AIC US$/oz 1,127 1,091 3 %
Sustaining capital expenditure US$m 45.8 55.4 (17)%
Non-sustaining capital expenditure US$m – %
Total capital expenditure US$m 45.8 55.4 (17)%

Gold production decreased by 5% to 129,100oz in the December quarter from 135,700oz in the September quarter due to lower tonnes processed and lower yield. Yield decreased by 2% to 1.18g/t in the December quarter from 1.21g/t in the September quarter due to lower grade ore mined and processed. In the December quarter, 0.5Mt stockpiles at 0.84g/t were processed compared with 0.5Mt stockpiles at 0.85g/t in the September quarter, while ex-pit ore processed in the December quarter was 2.9Mt at 1.31g/t compared with 3Mt at 1.35g/t in the September quarter.

Total tonnes mined, including capital waste stripping, decreased by 12% to 21.2Mt in the December quarter from 24.1Mt in the September quarter in line with the mining sequence. Ore mined increased by 17% to 3.5Mt in the December quarter from 3.0Mt in the September quarter due to increased ore mining from Kobada and Teberebie pits. Capital waste stripped decreased by 38% to 9.5Mt in December quarter from 15.4Mt in the September quarter in line with the 2021 production schedule. Operational waste increased by 41% to 8.1Mt in the December quarter from 5.7Mt in the September quarter in line with the increased ore tonnes mined. Strip ratio decreased by 29% to 5.0 in the December quarter from 7.0 in the September quarter due to the lower capital strip in line with the mining schedule. Gold mined increased by 13% to 149.8koz in the December quarter from 132.9koz in the September quarter due to higher ore tonnes mined.

Tonnes processed decreased by 3% to 3,401kt in the December quarter from 3,493kt in the September quarter due to downtime on the SAG mill as a result of a motor change out and the replacement of a torn mill feed conveyor.

All-in cost increased by 3% to US$1,127/oz in the December quarter from US$1,091/oz in the September quarter due to higher cost of sales before amortisation and depreciation as a result of higher operational tonnes mined and lower gold sold, partially offset by lower capital expenditure.

Capital expenditure decreased by 17% to US$46m in the December quarter from US$55m in the September quarter mainly due to lower capital waste tonnes mined.

Damang

    Dec 2021 Sept 2021 % Variance
   
Ore mined 000 tonnes 2,046 1,948 5 %
Waste (Capital) 000 tonnes 810 173 368 %
Waste (Operational) 000 tonnes 3,672 3,570 3 %
Total waste mined 000 tonnes 4,482 3,743 20 %
Total tonnes mined 000 tonnes 6,528 5,691 15 %
Strip ratio waste/ore 2.2 1.9 16 %
Grade mined g/t 1.54 1.40 10 %
Gold mined 000'oz 101.4 87.8 15 %
Tonnes milled 000 tonnes 1,201 1,167 3 %
Yield g/t 1.67 1.50 11 %
Gold produced 000'oz 64.5 56.4 14 %
Gold sold 000'oz 64.5 56.4 14 %
AISC US$/oz 885 823 8 %
AIC US$/oz 915 879 4 %
Sustaining capital expenditure US$m 7.3 4.3 70 %
Non-sustaining capital expenditure US$m 0.2 1.5 (87)%
Total capital expenditure US$m 7.5 5.8 29 %

Gold production increased by 14% to 64,500oz in the December quarter from 56,400oz in the September quarter due to higher yield and mill throughput. Yield increased by 11% to 1.67g/t in the December quarter from 1.50g/t in the September quarter due to higher mined and feed grade.

Total tonnes mined increased by 15% to 6.5Mt in the December quarter from 5.7Mt in the September quarter. Ore tonnes mined increased by 5% to 2.0Mt in the December quarter from 1.9Mt in the September quarter in line with the strategy to mine more ore and preferentially process higher grade ore and stockpile lower grade material. Mined grade increased by 10% to 1.54g/t in the December quarter from 1.40g/t in the September quarter due to mining in more consistent mineralised ore zones within the Banket Conglomerate and Banket Footwall sandstone of DPCB. Operational waste tonnes mined increased by 3% to 3.7Mt in the December quarter from 3.6Mt in the September quarter in line with the higher volumes mined. Capital waste mined increased by 368% to 0.8Mt in the December quarter from 0.2Mt in the September quarter due to the increased mining rate at the Huni pit.

Strip ratio increased by 16% to 2.2 in the December quarter from 1.9 in the September quarter due to the increased waste stripping in the Huni pit.

All-in cost increased by 4% to US$915/oz in the December quarter from US$879/oz in the September quarter mainly due to higher capital expenditure on the Huni waste stripping and higher cost of sales before amortisation and depreciation, partially offset by higher gold sales.

Total capital expenditure increased by 29% to US$8m in the December quarter from US$6m in the September quarter. Sustaining capital expenditure increased by 70% to US$7m in the December quarter from US$4m in the September quarter due to expenditure on Huni waste stripping. Non-sustaining capital expenditure decreased by 87% to US$0m in the December quarter from US$2m in the September quarter due to timing of the spend on the Far East Tailings Storage Facility (FETSF) stage 3 raise.

Asanko (Equity accounted Joint Venture)

    Dec 2021 Sept 2021 % Variance
   
Ore mined 000 tonnes 1,623 1,464 11 %
Waste (Capital) 000 tonnes 517 559 (8)%
Waste (Operational) 000 tonnes 8,235 9,458 (13)%
Total waste mined 000 tonnes 8,752 10,017 (13)%
Total tonnes mined 000 tonnes 10,375 11,481 (10)%
Strip ratio waste/ore 5.4 6.8 (21)%
Grade mined g/t 1.24 1.33 (7)%
Gold mined 000'oz 64.9 62.7 4 %
Tonnes milled 000 tonnes 1,472 1,542 (5)%
Yield g/t 1.06 1.00 6 %
Gold produced 000'oz 50.3 49.5 2 %
Gold sold 000'oz 51.4 48.4 6 %
AISC US$/oz 1,539 1,598 (4)%
AIC US$/oz 1,680 1,697 (1)%
Sustaining capital expenditure US$m 7.3 11.0 (34)%
Non-sustaining capital expenditure US$m 5.0 1.4 257 %
Total capital expenditure US$m 12.3 12.4 (1)%

All figures in table on a 100% basis.

Gold production increased by 2% to 50,300oz (100% basis) in the December quarter from 49,500oz (100% basis) in the September quarter mainly due to higher yield. The higher yield is mainly due to slightly improved plant recovery as a lower volume of the transition ore characterised by high organic carbon content was treated. The mill feed in the December quarter was sourced primarily from Esaase pit, Akwasiso cut 3 and lower grade stockpiles.

Total tonnes mined decreased by 10% to 10.4Mt in the December quarter from 11.5Mt in the September quarter. Waste tonnes mined decreased by 13% to 8.8Mt in the December quarter from 10.0Mt in the September quarter due to a reduced strip ratio at Esaase pit. Ore tonnes mined increased by 11% to 1.6Mt in the December quarter from 1.5Mt in the September quarter with ore tonnes sourced primarily from the Esaase pit. Continued stripping at Akwasiso cut 3 during the December quarter assisted to contribute some ore to the plant.

All-in cost decreased by 1% to US$1,680/oz in the December quarter from US$1,697/oz in the September quarter mainly due to higher gold sold.

Total capital expenditure was similar at US$12m in the December quarter.

Sustaining capital expenditure decreased by 34% to US$7m in the December quarter from US$11m in the September quarter mainly due to a lower charge back from deferred striping. Non-sustaining capital expenditure increased by 257% to US$5m in the December quarter from US$1m in the September quarter mainly due to timing of expenditure on Akwasiso Cut 3, Obotan Water treatment plant and others.

South America region

Peru

Cerro Corona

      Dec 2021 Sept 2021 % Variance
     
Ore mined 000 tonnes 3,047 2,880 6 %
Waste mined 000 tonnes 3,167 5,705 (44)%
Total tonnes mined 000 tonnes 6,214 8,585 (28)%
Grade mined – gold g/t 0.78 0.77 1 %
Grade mined – copper per cent 0.43 0.42 2 %
Gold mined 000'oz 76.6 71.3 7 %
Copper mined 000 tonnes 13,015 12,038 8 %
Tonnes milled 000 tonnes 1,736 1,746 (1)%
Gold recovery per cent 71.4 64.7 10 %
Copper recovery per cent 89.1 87.0 2 %
Yield – Gold g/t 0.72 0.60 20 %
  – Copper per cent 0.46 0.42 10 %
  – Combined eq g/t 1.43 1.24 15 %
Gold produced 000'oz 38.4 32.3 19 %
Copper produced tonnes 7,617 7,083 8 %
Total equivalent gold produced 000' eq oz 79.6 69.4 15 %
Total equivalent gold sold 000 'eq oz 85.0 59.9 42 %
AISC US$/oz (138) 24 (675)%
AISC US$/eq oz 853 805 6 %
AIC US$/oz 63 342 (82)%
AIC eq oz 953 951 – %
Sustaining capital expenditure US$m 11.6 9.0 29 %
Non-sustaining capital expenditure US$m 7.9 8.5 (7)%
Total capital expenditure US$m 19.5 17.5 11 %

Gold equivalent production increased by 15% to 79,600oz in the December quarter from 69,400oz in the September quarter mainly due to higher gold and copper grades and higher gold and copper recoveries as a result of better metallurgical conditions.

Total tonnes mined decreased by 28% to 6.2Mt in the December quarter from 8.6Mt in the September quarter mainly due to a decrease in waste mined of 44% to 3.2Mt in the December quarter from 5.7Mt in the September quarter. This was partially offset by an increase in ore mined of 6% to 3.0Mt in the December quarter from 2.9Mt in the September quarter. The decrease in total tonnes mined is in line with the mining schedule, considering the start of the rainy season during the December quarter.

Gold and copper grades mined increased by 1% and 2% respectively, in line with the revised mining sequence following the slope instability issue in the eastern section of the pit in H1 2021. Consequently, gold yield increased by 20% to 0.72g/t in the December quarter from 0.60g/t in the September quarter and copper yield increased by 10% to 0.46% in the December quarter from 0.42% in the September quarter, both explained by an increase in grades processed and recoveries.

Total equivalent gold sold increased by 42% to 85,000oz in the December quarter from 59,900oz in the September quarter mainly due to higher gold and copper production and lower concentrate stock at the end of December due to the sales schedule.

All-in cost per gold ounce sold decreased by 82% to US$63/oz in the December quarter from US$342/oz in the September quarter mainly explained by a higher copper by-product credit due to a higher copper price and higher copper sold, as well as higher gold ounces sold, partially offset by higher cost of sales before amortisation and depreciation and higher capital expenditure. All-in cost per equivalent ounce increased marginally to US$953 per equivalent ounce in the December quarter from US$951 per equivalent ounce in the September quarter.

Unplanned COVID-19 related expenditure amounted US$2.2m in the December quarter compared to US$2.8m in the September quarter.

Total capital expenditure increased by 11% to US$20m in the December quarter from US$18m in the September quarter.

Sustaining capital expenditure increased by 29% to US$12m in the December quarter from US$9m in the September quarter mainly due to the replacement of the crusher in the process plant and land acquisition near the east wall of the pit. Non-sustaining capital expenditure decreased by 7% to US$8m in the December quarter from US$9m in the September quarter due to lower construction activities at the Arpon and Ana waste storage facilities, mainly explained by the rainy season.

Chile

Salares Norte

Salares Norte construction continued to be impacted by the indirect effects of COVID-19 during Q4 2021, with work force availability being a challenge. Despite this, the total project progressed 12.3% during the quarter, slightly behind plan of 14.0% but improving on the 8.3% achieved in Q3 2021.

US$109.7m was spent on the project during the December quarter, comprised of US$134.3m in capex, US$9.9m in exploration and US$6.0m in other costs, partially offset by a US$38.7m release of working capital and a credit of US$1.8m from the realised portion of the FX hedge.

Good progress was made with construction of the processing plant during Q4 2021. The SAG and Ball mill shells and heads were installed during the quarter, with the gear installation now underway. Structural steel installation at the grinding area continued during Q4 and the bridge crane was commissioned. The installation of all leaching tanks and some of the CIP tanks progressed during the December quarter. The steel structures and tank plates of all of the thickeners were completed by the end of the year and the installation of the mechanical components is underway.

Pre-stripping of the Brecha Principal pit continued to track slightly ahead of plan during Q4 2021, with 10.1Mt moved compared to 6.6Mt in the previous quarter.

US$9.9m was spent on district exploration during the December quarter compared to US$4.7m spent in the September quarter. Total metres drilled in the December quarter were 9,105 metres compared to 3,244 metres drilled in the September quarter.

In December 2021, Gold Fields was informed by the Chilean regulators that they had begun sanction proceedings against Salares Norte regarding the chinchilla relocation process. We continue to collaborate with the authorities to resolve the sanction proceedings and ensure that the relocation process can commence. Importantly, the delay in the relocation does not in any way affect the construction schedule at Salares Norte.

Australia region

St Ives

    Dec 2021 Sept 2021 % Variance
   
Underground        
Ore mined 000 tonnes 453 514 (12)%
Waste mined 000 tonnes 244 224 9 %
Total tonnes mined 000 tonnes 697 738 (6)%
Grade mined g/t 4.92 5.01 (2)%
Gold mined 000'oz 71.7 82.9 (14)%
Surface        
Ore mined 000 tonnes 295 474 (38)%
Surface waste (Capital) 000 tonnes 801 1,500 (47)%
Surface waste (Operational) 000 tonnes 303 537 (44)%
Total waste mined 000 tonnes 1,104 2,037 (46)%
Total tonnes mined 000 tonnes 1,399 2,511 (44)%
Grade mined g/t 1.91 1.79 7 %
Gold mined 000'oz 18.1 27.3 (34)%
Strip ratio waste/ore 3.7 4.3 (14)%
Total (Underground and Surface)        
Total ore mined 000 tonnes 748 988 (24)%
Total grade mined g/t 3.74 3.47 8 %
Total tonnes mined 000 tonnes 2,096 3,250 (36)%
Total gold mined 000'oz 89.8 110.2 (19)%
Tonnes milled 000 tonnes 1,015 1,025 (1)%
Yield – underground g/t 4.93 4.28 15 %
Yield surface g/t 1.44 1.53 (6)%
Yield combined g/t 3.39 2.85 19 %
Gold produced 000'oz 110.5 94.0 18 %
Gold sold 000'oz 108.6 94.0 16 %
AISC A$/oz 1,339 1,302 3 %
US$/oz 978 955 2 %
AIC A$/oz 1,387 1,358 2 %
US$/oz 1,013 996 2 %
Sustaining capital expenditure A$m 29.0 31.7 (9)%
US$m 21.1 23.3 (9)%
Non-sustaining capital expenditure A$m 5.2 5.2 – %
US$m 3.8 3.9 (3)%
Total capital expenditure A$m 34.2 36.9 (7)%
US$m 24.9 27.2 (8)%

Gold production increased by 18% to 110,500oz in the December quarter from 94,000oz in the September quarter due to increased yield of underground ore processed.

Ore mined from the underground mines decreased by 12% to 453,000t in the December quarter from 514,000t in the September quarter in line with the planned mining schedule.

Gold mined decreased by 14% to 71,700oz in the December quarter from 82,900oz in the September quarter due to lower ore tonnes and grade mined.

In the open pits, ore mined decreased by 38% to 295,000t in the December quarter from 474,000t in the September quarter with the completion of ore mining from the Delta Island open pit at the end of December.

Capital waste tonnes mined decreased by 47% to 801,000t in the December quarter from 1,500,000t in the September quarter following the completion of pre-stripping of Delta Island open pit at the end of the September quarter and commencement of pre-strip activities at Neptune stage 7 in the December quarter.

Operational waste tonnes mined decreased by 44% to 303,000t in the December quarter from 537,000t in the September quarter following reduced tonnes mined at Delta Island open pit in the December quarter, as the pit neared the end of its life.

As a result of the decrease in open pit ore and waste mined, gold mined in the open pits decreased by 34% to 18,100oz in the December quarter from 27,300oz in the September quarter. With the Delta Island pit being completed and significant stockpiles being available, some of the open pit mining fleet was utilised in undertaking progressive rehabilitation of historical waste dumps and causeways.

All-in cost increased by 2% to A$1,387/oz (US$1,013/oz) in the December quarter from A$1,358/oz (US$996/oz) in the September quarter due to increased cost of sales before amortisation and depreciation as a result of a gold inventory charge to cost of A$13.7m (US$10.3m) in the December quarter with less ore mined than processed, compared with a gold inventory credit to cost of A$17.3m (US$13.2m) in the September quarter with more ore mined than processed. This increased cost of sales before amortisation and depreciation was partially offset by increased gold sales and lower capital expenditure.

Total capital expenditure decreased by 7% to A$34m (US$25m) in the December quarter from A$37m (US$27m) in the September quarter.

Sustaining capital expenditure decreased by 9% to A$29m (US$21m) in the December quarter from A$32m (US$23m) in the September quarter due to a decrease in exploration drilling during the December quarter.

Non-sustaining capital expenditure in the December quarter was similar at A$5m (US$4m).

Agnew

    Dec 2021 Sept 2021 % Variance
   
Underground ore mined 000 tonnes 266 260 2 %
Underground waste mined 000 tonnes 208 220 (5)%
Total tonnes mined 000 tonnes 474 480 (1)%
Grade mined underground g/t 7.11 6.11 16 %
Gold mined 000'oz 60.8 51.2 19 %
Tonnes milled 000 tonnes 320 307 4 %
Yield g/t 5.58 5.44 3 %
Gold produced 000'oz 57.5 53.8 7 %
Gold sold 000'oz 57.1 53.1 8 %
AISC A$/oz 1,500 1,651 (9)%
US$/oz 1,091 1,214 (10)%
AIC A$/oz 1,782 1,800 (1)%
US$/oz 1,299 1,322 (2)%
Sustaining capital expenditure A$m 18.1 20.4 (11)%
US$m 13.1 15.0 (13)%
Non-sustaining capital expenditure A$m 16.1 7.9 104 %
US$m 11.9 5.8 105 %
Total capital expenditure A$m 34.2 28.3 21 %
US$m 25.0 20.8 20 %

Gold production increased by 7% to 57,500oz in the December quarter from 53,800oz in the September quarter due to increased grade of ore mined and processed and an increase in tonnes milled.

Mined grade increased by 16% to 7.11g/t in the December quarter from 6.11g/t in the September quarter with high grade ore mined from the Kath Lode area at Waroonga during the December quarter. As a result of the increase in grade, gold mined increased by 19% to 60,800oz in the December quarter from 51,200oz in the September quarter.

All-in cost decreased by 1% to A$1,782/oz (US$1,299/oz) in the December quarter from A$1,800/oz (US$1,322/oz) in the September quarter due to increased gold sold, partially offset by higher capital expenditure.

Total capital expenditure increased by 21% to A$34m (US$25m) in the December quarter from A$28m (US$21m) in the September quarter.

Sustaining capital expenditure decreased by 11% to A$18m (US$13m) in the December quarter from A$20m (US$15m) in the September quarter due to lower mine development at Waroonga. Non-sustaining capital expenditure increased by 104% to A$16m (US$12m) in the December quarter from A$8m (US$6m) in the September quarter with increased expenditure on the mill crushing circuit expansion.

Granny Smith

    Dec 2021 Sept 2021 % Variance
   
Underground ore mined 000 tonnes 424 404 5 %
Underground waste mined 000 tonnes 240 278 (14)%
Total tonnes mined 000 tonnes 664 682 (3)%
Grade mined – underground g/t 6.01 6.69 (10)%
Gold mined 000'oz 81.9 87.0 (6)%
Tonnes milled 000 tonnes 438 400 10 %
Yield
g/t 5.62 6.13 (8)%
Gold produced 000'oz 79.1 78.9 – %
Gold sold 000'oz 79.1 82.0 (4)%
AISC A$/oz 1,378 1,186 16 %
US$/oz 1,007 873 15 %
AIC
A$/oz 1,550 1,378 12 %
US$/oz 1,133 1,015 12 %
Sustaining capital expenditure A$m 29.3 22.5 30 %
US$m 21.6 16.7 29 %
Non-sustaining capital expenditure A$m 13.6 15.7 (13)%
US$m 9.9 11.7 (15)%
Total capital expenditure A$m 42.9 38.2 12 %
US$m 31.5 28.4 11 %

Gold production in the December quarter was 79,100oz, similar to gold production of 78,900oz in the September quarter.

Underground waste mined decreased by 14% to 240kt in the December quarter from 278kt in the September quarter due to decreased development in zones Z60-100 and Z120.

Grade mined decreased by 10% to 6.01g/t in the December quarter from 6.69g/t in the September quarter due to decreased development and stoping grades in zones Z110 and Z120.

Tonnes milled increased by 10% to 438kt in the December quarter from 400kt in the September quarter due to increased availability of fresh rock from underground, combined with 14kt of ore processed from existing stockpiles.

All-in cost increased by 12% to A$1,550/oz (US$1,133/oz) in the December quarter from A$1,378/oz (US$1,015/oz) in the September quarter due to increased production cost (increased ore mined and processed), lower gold sold and increased capital expenditure.

Total capital expenditure increased by 12% to A$43m (US$32m) in the December quarter from A$38m (US$28m) in the September quarter.

Sustaining capital expenditure increased by 30% to A$29m (US$22m) in the December quarter from A$23m (US$17m) in the September quarter, with A$6m (US$4m) spent on new mobile equipment in the December quarter (September quarter Nil). Non-sustaining capital expenditure decreased by 13% to A$14m (US$10m) in the December quarter from A$16m (US$12m) in the September quarter due to decreased expenditure on the second decline.

Gruyere

    Dec 2021 Sept 2021 % Variance
   
Mine physicals and AIC in table on a 100% basis    
Ore mined 000 tonnes 3,164 2,591 22 %
Waste (Capital) 000 tonnes 6,602 6,432 3 %
Waste (Operational) 000 tonnes 939 1,384 (32)%
Total waste mined 000 tonnes 7,541 7,816 (4)%
Total tonnes mined 000 tonnes 10,705 10,407 3 %
Grade mined g/t 1.00 0.88 14 %
Gold mined 000'oz 101.2 73.5 38 %
Strip ratio waste/ore 2.4 3.0 (20)%
Tonnes milled 000 tonnes 2,236 2,101 6 %
Yield g/t 0.94 0.88 7 %
Gold produced 000'oz 67.8 59.4 14 %
Gold sold 000'oz 66.9 60.7 10 %
AISC A$/oz 1,453 1,716 (15)%
US$/oz 1,058 1,267 (16)%
 
AIC A$/oz 1,465 1,736 (16)%
US$/oz 1,067 1,281 (17)%
 
Capital in table on a 50% basis      
Sustaining capital expenditure 50% basis A$m 14.5 14.2 2 %
US$m 10.5 10.5 %
Non-sustaining capital expenditure – 50% basis A$m 0.4 0.6 (33)%
US$m 0.3 0.4 (25)%
Total capital expenditure – 50% basis A$m 14.9 14.8 1 %
US$m 10.8 10.9 (1)%

Gold production increased by 14% to 67,800oz in the December quarter from 59,400oz in the September quarter due to increased tonnes milled as well as an increase in grade of ore processed.

Ore mined increased by 22% to 3.16Mt in the December quarter from 2.59Mt in the September quarter with 0.62Mt of additional ore mined from stage 3 of the Gruyere pit.

Operational waste tonnes mined decreased by 32% to 0.94Mt in the December quarter from 1.38Mt in the September quarter due to less waste mined from stage 2 of the Gruyere pit.

Grade mined increased by 14% to 1.00g/t in the December quarter from 0.88g/t in the September quarter driven by an increase in grade of ore mined from stage 2 of the Gruyere pit.

As a result of the increased ore mined and the increase in grade, gold mined increased by 38% to 101,200oz in the December quarter from 73,500oz in the September quarter.

All-in cost decreased by 16% to A$1,465/oz (US$1,067/oz) in the December quarter from A$1,736/oz (US$1,281/oz) in the September quarter due to increased gold sold and a GIP credit of A$6m (US$5m) in the December quarter compared to a credit of A$1m (US$1m) in the September quarter.

Total capital expenditure (on a 50% basis) increased by 1% to A$15m (US$11m) in the December quarter from A$15m (US$11m) in the September quarter. Sustaining capital expenditure (on a 50% basis) increased by 2% to A$15m (US$11m) in the December quarter from A$14m (US$11m) in the September quarter due to timing of expenditure relating to the tailings storage facility. Non-sustaining capital expenditure decreased by 33% to nil in the December quarter from A$1m (US$0m) in the September quarter.