St Barbara : Quarterly Report Q3 FY22

Q3 March FY22

3 months to 31 March 2022

Highlights Q3 March FY221

• • Group gold production of 61,819 ounces with All-In Sustaining Cost (AISC) of A$2,290 per ounce

• • Acquisition of Bardoc Gold has increased Group Mineral Resources by 3.0Moz

• • Early preparatory work on Zoroastrian mine complete, bringing forward commencement of decline construction to Q3 FY23

  • • First ore from Zoroastrian mine now anticipated six months earlier2 in Q1 FY24 with first full year of production expected to contribute 30koz of gold production from ~300kt at an average 3.5g/t

  • • First ore from Aphrodite mine expected H1 FY25 with first full year of production expected to contribute 90koz of gold production from ~900kt at an average 3.5g/t

• • Continued positive drill results in Old South Gwalia support continuity from 600 metres below surface (mbs) to 1000mbs included:

  • • UGD2860A: 31m @ 3.27g/t Au at 593mbs

  • • UGD2861: 25m @ 2.25g/t Au at 590mbs

  • • Updated Mineral Resource targeted for completion during Q1 FY23

• • Rehabilitation of fall of ground event at Gwalia complete ensuring access to high grade stopes in Q4 FY22

Production summary

Q3 Mar	Q4 Jun	Q1 Sep	Q2 Dec	Q3 Mar	YTD
FY21	FY21	FY22	FY22	FY22	FY22
Group TRIFR3	mhrs	3.7	3.9	3.6	2.7	2.8	2.8
Gold Production	koz	82	83	67	66	62	194
All-In Sustaining Cost	A$/oz	1,649	1,623	1,492	1,587	2,290	1,778
Gold Sold	koz	71	96	58	76	56	191
Realised Gold Price	A$/oz	2,247	2,336	2,408	2,423	2,475	2,434

St Barbara Managing Director and CEO Craig Jetson said, "St Barbara remains positioned to deliver on our updated full year guidance and growth opportunities, despite marginally lower quarter on quarter production achieved in the March period. Our Leonora Operations were impacted by ongoing skilled labour shortages in Western Australia which the team has done a great job managing but we remain conscious that it is an evolving landscape which requires constant management. At Simberi our return to operations were interrupted by a COVID-19 outbreak on the island which temporarily raised operating costs and lowered production.

Consistent with our Province strategy, we have successfully completed our acquisition of Bardoc Gold, locking in the acceleration of the Leonora Province Plan. This positions Leonora as a significant processing hub in the Western Australian goldfields. Further encouraging drilling results were achieved in the Old South Gwalia ore body, which has the potential to add new mining fronts higher in the mine. An updated Mineral Resource for this area of the mine is anticipated to be completed during Q1 FY23.

1

This report uses certain Non-IFRS measures as set out on the last page of this report. Unless otherwise noted, information in this report that relates to Mineral Resources or Ore Reserves is extracted from the report titled 'Ore Reserves and Mineral Resources Statements 30 June 2021' released to the ASX on 26 August 2021. This report has not been audited.

2 Earlier than original forecast see market release "Strategic acquisition of Bardoc Gold accelerates Leonora Province Plan" released to the ASX on 20 December 2021.

3

Total Recordable Injury Frequency Rate rolling 12-month average, mhrs - injuries per million hours.

During the quarter I was able to make my first trip to our Atlantic Operations where I have been able to personally connect with First Nations groups and the new government in Halifax as we work towards permits for Beaver Dam and Fifteen Mile Stream mines. I look forward to further engagement when I return next month.

Importantly, our growth and production results were achieved against a backdrop of strong safety results in the quarter with TRIFR of 2.8 per million hours worked."

Overview

Group gold production for the March quarter was 6% lower than the prior quarter. Leonora's production was impacted by lower grade and lower third party ore volumes while Atlantic's production was hindered by lower grades from the Touquoy pit and more severe than usual winter weather conditions. This reduction was largely offset by the resumption of production at Simberi.

The ramp up of production at Simberi, following the successful installation of the deep sea tailings placement pipeline early in the quarter, was impacted by the escalation of COVID-19 case numbers at site. With the outbreak under control in the latter part of the quarter, St Barbara reinstated updated production guidance for FY22, which had been withdrawn earlier. The surge in case numbers impacted maintenance personnel in particular, the net result of which is a backlog of mobile fleet maintenance activity that is likely to impact production in the near term.

Group All-In Sustaining Cost for the December quarter was A$2,290 per ounce due to the interrupted ramp-up of production at Simberi and lower grade ore at Atlantic.

As at 31 March 2022, St Barbara's total cash at bank position was A$79 million (down from A$94 million on 31 December 2021). Total debt owing under the Company's syndicated facility on 31 March 2022 remains unchanged at C$80 million and A$50 million.

St Barbara remains on track to achieve its FY22 updated production guidance.

St Barbara was again recognised as an Employer of Choice for Gender Equality by the Australian Workplace Gender Equality Agency for the eighth year running and likewise included in the global Bloomberg Gender Equality Index (GEI) for the second consecutive year.

On 13 April 2022, St Barbara completed the acquisition of all the issued shares of Bardoc Gold through the implementation of a scheme of arrangement (Scheme). The new St Barbara shares issued under the Scheme commenced trading on 14 April 2022. The acquisition underpins St Barbara's intention to accelerate the Leonora Province Plan through the development of the advanced Aphrodite and Zoroastrian underground deposits.

Consolidated Gold Production & Guidance

• 4 C$1,500 to C$1,685 per ounce at AUD/CAD of 0.91

• 5 US$2,400 to US$2,700 per ounce at AUD/USD of 0.75

Q3 Mar	Q4 Jun	Q1 Sep	Q2 Dec	Q3 Mar	YTD	Guidance
FY21	FY21	FY22	FY22	FY22	FY22	FY22
Qtr to	Qtr to	Qtr to	Qtr to	Qtr to	9 months to	Year to
31 Mar 2021	30 Jun 2021	30 Sep 2021	31 Dec 2021	31 Mar 2022	31 Mar 2022	30 June 2022
Atlantic	oz	20,606	26,718	15,243	16,887	11,006	43,136	55-65 koz
Leonora	oz	42,716	45,157	51,757	48,637	40,559	140,953	180-200 koz
Simberi	oz	18,981	10,824	-	-	10,254	10,254	25-30 koz
Consolidated	oz	82,303	82,698	67,000	65,524	61,819	194,343	275-290 koz
Mined Grade
Atlantic	g/t	0.71	0.91	0.63	0.76	0.52	0.64	n/a
Leonora	g/t	8.0	6.5	8.6	6.8	6.1	7.1	n/a
Simberi	g/t	1.33	1.47	1.41	1.29	1.21	1.24	n/a
Total Cash Op. Costs
Atlantic	A$/oz	903	769	1,188	1,234	1,799	1,360	n/a
Leonora	A$/oz	1,047	1,274	1,033	1,164	1,341	1,165	n/a
Simberi	A$/oz	2,032	2,835	-	-	3,829	3,829	n/a
Consolidated	A$/oz	1,237	1,314	1,071	1,184	1,861	1,362	n/a
All-In Sustaining Cost
Atlantic	A$/oz	1,128	1,011	1,504	1,396	2,013	1,590	1,650-1,8504
Leonora	A$/oz	1,555	1,663	1,488	1,653	1,916	1,668	1,605-1,720
Simberi	A$/oz	2,426	2,964	-	-	4,064	4,064	3,200-3,6005
Consolidated	A$/oz	1,649	1,623	1,492	1,587	2,290	1,778	1,750-1,870
Page 3 of 68

Production Summary

Consolidated

St Barbara's financial year is

1 July to 30 June

Production

Leonora Operations, Leonora, Western Australia

Production Summary Ore Mined

Q3 Mar FY21

Q4 Jun FY21

Q1 Sep FY22

Q2 Dec FY22

Q3 Mar FY22

YTD FY22

Waste mined Mined grade

Ore milled6 Milled grade6 Recovery

kt kt g/t kt g/t %

168

195

179

193

194

566

73

71

105

42

64

211

8.0

6.5

8.6

6.8

6.1

7.1

194

281

244

279

254

777

7.1

5.2

6.8

5.6

5.2

5.8

97

96

97

97

96

97

Gold production Gold sold Realised gold price

oz oz

A$/oz

42,716 36,864 2,298

45,157 49,597 2,348

51,757 45,472 2,439

48,637 55,600 2,453

40,559 37,566 2,511

140,953 138,638 2,464

All-In Sustaining Cost (AISC)

A$/oz produced

1,555

1,663

1,488

1,653

Operations

Leonora's gold production of 40.6koz was 17% lower than the prior quarter, primarily driven by reduced mill throughput, head grade and gold production from purchased ore. During the quarter, ore purchased from the Linden Gold Alliance contributed 3,178 oz of gold in group production representing a decrease of 33% over prior quarter due to lower grades in the delivered ore.

In November 2021, there was a fall of ground at Gwalia which blocked access to high grade stopes requiring a change to the near-term mine plan. Despite ore production from the mine being in line with the prior quarter, the rehabilitation of high grade stopes carried over into Q3. This required the continued mining of lower grade stopes, impacting the mined grade for the quarter. A bypass crosscut has been completed and the original ore-drive support is currently being upgraded, with the mining front to be re-established in Q4.

Labour shortages exacerbated by COVID-19 restrictions in Western Australia have had significant impact on development meters. St Barbara remains aware that access to skilled labour is at risk for the foreseeable future as the economy transitions to living with the pandemic. Three new jumbo development drills have been delivered to site to accelerate development metres.

Mill throughput was 9% lower than the prior quarter, resulting from the processing of lower volumes of purchased and stockpiled ore, and increased scheduled mill downtime.

Lower grades from the Gwalia underground due to mining of lower grade stopes compared to the prior quarter and lower grades from purchased and stockpiled ore, resulted in an 8% decrease in milled grade from the prior quarter.

Leonora achieved an AISC of A$1,916 per ounce, an increase of 16% over the December quarter. This was principally driven by the reduced gold production due to lower head grades and mill throughput.

Sustaining capital guidance for Leonora operations in FY22 has been lowered from A$65-75m to A$55-65m due to lower than expected truck and jumbo utilisation and availability stemming from skilled labour shortages in Western Australia. Deferred sustaining work is planned for completion in the first half of FY23.

Bardoc Gold acquisition completed

On 13 April 2022, St Barbara completed the acquisition of Bardoc Gold with the successful implementation of the Scheme. The acquisition delivers St Barbara ownership of the advanced Aphrodite and Zoroastrian underground deposits.

Due to their proximity to road and rail infrastructure that connect them to Leonora, the deposits will become additional ore sources which will accelerate the Leonora Province Plan by filling the Leonora mill sooner than previously expected.

At the Zoroastrian underground deposit St Barbara, in collaboration with Bardoc Gold, was able to commence project establishment works ahead of initial expectations, including work on approvals, infrastructure design and geotechnical

6 Includes Gwalia mineralised waste, stockpile material and third party ore purchases.

assessment. Geotechnical drilling is expected to occur in May 2022. This early progress allows St Barbara to now target construction of surface works and contractor mobilisation ahead of schedule in Q2 FY23 (previously Q3 FY23) and portal construction in Q3 FY23 (previously Q4 FY23). First ore from Zoroastrian is now targeted to be brought forward to Q1 FY24 from H2 FY24.

Current Resources at Zoroastrian are anticipated to supply at least three years of ore to the Leonora processing plant. With the orebody open in all directions, St Barbara intends to move quickly to drill targeted extensions of the Resource once drill locations have been established off the decline.

Development of the refractory Aphrodite underground deposit will be timed to coincide with installation of refractory ore treatment capability at the Leonora processing plant. Aphrodite is a high margin refractory ore source that will complement the Harbour Lights refractory deposit which has also recently been confirmed to be amenable to the Glencore Albion Process™ installation being planned for the Leonora processing plant.

Work on Aphrodite progressed over the quarter and drilling for geotechnical and metallurgical test work purposes is expected to commence in May 2022. Construction of the Aphrodite underground mine continues to be targeted to commence in Q1 September FY24 at an estimated capital cost of ~A$30 million7.

Accelerated development plan

Event	Initial target date	Updated target date
Feasibility Study for Leonora mill expansion to 2.1Mtpa & Refractory ore processing complete	Q2 FY23	Q3 FY23
Mobilisation of mining contractor for Aphrodite and Zoroastrian underground mines	Q3 FY23	Q2 FY23
Commence construction of Leonora expansion to 2.1Mtpa with Refractory ore processing capability	Q3 FY23
Construction of Zoroastrian underground mine portal commences	Q4 FY23	Q3 FY23
Construction of Aphrodite underground mine portal commences	Q1 FY24
Zoroastrian underground mine first ore	H2 FY24	Q1 FY24
Leonora processing plant expansion to 2.1Mtpa complete	Q4 FY24
Aphrodite underground mine & Leonora mill refractory ore processing commences	H1 FY25

Leonora Province Plan continues to advance

The combined pre-feasibility study (PFS) for Tower Hill and Harbour Lights continues to progress. The PFS is now expected to be completed in Q1 FY23 (previously Q4 FY22) after delays in accessing geotechnical and infill drilling locations for Tower Hill and Harbour Lights.

As previously noted, the PFS work is now focused on the most cost effective opportunity of expanding the Leonora processing plant capacity from 1.4Mtpa to 2.1Mtpa. Expanding the processing plant capacity by 50% is expected to be achieved by upgrading the conveyor drives in the crushing circuit, adding a second ball mill to the grinding circuit and the addition of intertank screens through an expanded carbon-in-leach (CIL) circuit.

Work is also underway in the PFS to incorporate the Glencore's Albion Process™. The proposed plant is being designed to be able to alternate between the treatment of refractory and free-milling ores. The ability to process refractory ore will be unique to the Leonora processing plant within a 200km radius, providing new opportunities for acquisition and discovery of refractory deposits.

During the quarter, the resource definition infill and geotechnical drilling campaign commenced (with results reported under the Exploration section below). The infill drilling at Harbour Lights is being supplemented by a campaign log and sample up to 20kms of diamond drill core recovered from pre-1995 drilling to achieve greater definition on multi-element geological modelling to allow an updated resource for Harbour Lights in early FY23.

7 Subject to the outcome of the PFS and final studies