Oceanagold Provides Annual Resource and Reserve Statement Update
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MEDIA RELEASE
31 March 2020
OCEANAGOLD PROVIDES ANNUAL RESOURCE AND RESERVE STATEMENT
UPDATE
(MELBOURNE) OceanaGold Corporation ( TSX: OGC) (ASX: OGC ) (the “Company”) is pleased to provide
its updated annual Resource and Reserve (“R&R”) statement for the year ended December 31, 201 9.
Highlights
• Total Proven and Probable Reserves of 5.3 Moz of gold, 3. 5 Moz of silver and 0.16 Mt of copper,
with growth in gold reserves offsetting approximately half of 2019 mining depletion.
• Total Measured and Indicated Resources increased by approximately 0.80 Moz of gold year-on-year,
net of mining depletion.
• Inferred Resources increased approximately 0.7 Moz of gold year -on-year, net of mining depletion
largely due to first-time reporting of an Inferred Resource of 0.6 Moz for the Palomino underground
deposit at Haile and an additional 0.3 Moz for the WKP underground deposit near Waihi.
Michael Holmes, acting President and CEO of OceanaGold said, “Since 2015, we have focused on creating
value for shareholders by investing in organic growth initiatives including exploration. T hese investments
have yielded strong results, including the growth of Mineral Resources at the Martha Underground at Waihi,
the Horseshoe Underground at Haile, and the discovery of additional resources at WKP in New Zealand.”
“Since the acquisition of Waihi in 2015, o ur exploration team have delivered outstanding results through
drilling. We have increased the mine life at the Correnso Underground and added significant Indicated and
Inferred Resources at both Martha and WKP underground deposits.”
“WKP is expected to compliment Martha Underground over the long-term; it’s a game-changing prospect that
can leverage of f our existing infrastructure at Waihi . To-date, we have discovered 0.42 Moz gold in the
Indicated Resource category and 0.72 Moz of gold in the Inferred Resource category, at grades of 13 g/t and
12 g/t, respectively.”
As at December 31, 2019, the Company’s Proven and Probable (“P&P”) Reserves stood at 5.3 Moz of gold,
3.5 Moz of silver and 0.16 Mt of copper, representing on a consolidated basis, a 0.2 5 Moz year-on-year
decrease net of mining depletion of 0.51 Moz in 2019. Drilling-related reserve growth, largely for Macraes
and Haile open pits, offset over half of 2019 company-wide mining depletion.
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Table 1: Updated Mineral Reserves (as at December 31, 2019)
Figure 1: Changes to Proven & Probable Mineral Reserves
As at December 31, 2019, the Company’s Measured and Indicated ( “M&I”) Resources stood at 9. 4 Moz of
gold, 7. 7 Moz of silver and 0.17 Mt of copper. On a consolidated basis , the Company increased M&I
Resources by 0. 80 Moz, year -on-year net of mining depletion (0.51 Moz) , mainly due to d rilling-related
resource upgrades at the Waihi and Macraes operations.
Table 2: Updated Mineral Resources – Measured and Indicated (as at December 31, 2019)
PROJECT
AREA Cut-Off Mt Au g/t Ag g/t Cu % Mt Au g/t Ag g/t Cu % Mt Au g/t Ag g/t Cu % Au Moz Ag Moz Cu Mt
MACRAES Open Pit 0.40 g/t Au 12.3 1.04 . . 21.4 0.91 . . 33.7 0.96 . . 1.04 . .
MACRAES Underground 1.59 g/t Au 0.41 2.22 . . 0.51 1.76 . . 0.92 1.97 . . 0.06 . .
BLACKWATER
WAIHI Open Pit 0.5 g/t Au 0.16 3.05 30.5 . 0.66 2.91 29.1 . 0.81 2.94 29.4 . 0.08 0.77 .
WAIHI Underground 2.9 g/t Au 0.07 7.25 14.9 . 0.04 5.53 9.27 . 0.11 6.58 12.7 . 0.02 0.05 .
NEW ZEALAND 12.9 1.14 22.6 1.00 35.6 1.05 1.20 0.81 .
DIDIPIO Open Pit 0.40 g/t AuEq 23.3 0.33 1.99 0.29 . . . . 23.3 0.33 1.99 0.29 0.25 1.49 0.07
DIDIPIO Underground 1.34 g/t & 0.87 g/t AuEq 12.9 1.85 2.01 0.47 6.90 1.08 1.64 0.39 19.8 1.58 1.88 0.44 1.01 1.19 0.09
PHILIPPINES 36.2 0.87 6.9 1.08 43.1 0.91 1.26 2.68 0.16
HAILE Open Pit 0.50 g/t Au 12.3 2.03 . . 32.1 1.56 . . 44.5 1.69 . . 2.41 . .
Haile Underground 1.67 g/t Au . . . . 3.0 4.58 . . 3.0 4.58 . . 0.44 . .
USA 12.3 2.03 35.1 1.82 47.5 1.87 2.86 . .
TOTAL 61.4 1.16 64.7 1.45 126 1.31 5.31 3.49 0.16
Reported estimates of contained metal are not depleted for processing losses.
For underground reserves, cut-offs applied to diluted grades
For Didipio UG, incremental stopes proximal to development already planned to access main stoping areas are reported to a lower cut-off of 0.87 g/t AuEq
For Didipio, gold equivalence is based upon the presented gold and copper prices as well as processing recoveries. AuEq = Au g/t + 1.58 x Cu%
For Didipio the 23.3 Mt open pit stockpile inventory includes 5.3 Mt of low grade stocks mined at an approximate 0.27 g/t AuEq cut-off.
Mineral Reserves constrained to mine designs based upon US$1,300/oz gold, US$3.00/lb copper and US$17/oz silver. New Zealand reserves use 0.72 NZ/USD exchange rate
PROVEN PROBABLE PROVEN & PROBABLE
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Figure 2: Changes to Measured & Indicated Mineral Resources
Consolidated Inferred Resources, year -on-year, increased by 0.7 Moz to 4.3 Moz of gold, while silver and
copper resources were 3.9 Moz and 0.03 Mt, respectively. Increase to total Inferred Resources include the
first-time inclusion of an underground Inferred Resource for Palomino at Haile in the USA and increases due
to drilling-related resource upgrades for WKP at Waihi and Round Hill / Golden Point at Macraes in New
Zealand. These increases are over and above the successful conversion of Inferred Resources to Indicated
Resources.
Table 3: Updated Mineral Resources – Inferred Resource Statement (as at December 31, 2019)
PROJECT
AREA Cut-Off Mt Au g/t Ag g/t Cu % Mt Au g/t Ag g/t Cu % Mt Au g/t Ag g/t Cu % Au Moz Ag Moz Cu Mt
MACRAES Open Pit 0.30 g/t Au 22.5 1.03 . . 89.2 0.81 . . 112 0.86 . . 3.07 . .
MACRAES Underground 1.56 g/t Au 2.4 3.25 . . 1.5 2.64 . . 3.8 3.01 . . 0.37 . .
BLACKWATER
WAIHI Open Pit 0.5 g/t & 0.67 g/t Au 0.16 3.05 30.5 . 2.1 2.38 12.4 . 2.2 2.43 13.7 . 0.17 0.98 .
WAIHI Underground 2.15 g/t Au 0.07 7.25 14.9 . 6.0 6.55 20.0 . 6.0 6.55 19.9 . 1.27 3.86 .
NEW ZEALAND 25.1 1.27 98.7 1.22 124 1.23 4.89 4.84 .
DIDIPIO Open Pit 0.40 g/t AuEq 23.3 0.33 1.99 0.29 . . . . 23.3 0.33 1.99 0.29 0.25 1.49 0.07
DIDIPIO Underground 0.76 g/t & 1.16 g/t AuEq 12.4 1.99 2.14 0.50 9.6 1.07 1.63 0.39 22.1 1.59 1.92 0.45 1.13 1.36 0.10
PHILIPPINES 35.7 0.91 9.6 1.07 45.3 0.95 1.38 2.85 0.17
HAILE Open Pit 0.45 g/t Au 13.2 1.99 . . 37.5 1.48 . . 50.7 1.61 . . 2.63 . .
Haile Underground 1.44 g/t & 1.5 g/t Au . . . . 2.8 5.52 . . 2.8 5.52 . . 0.49 . .
USA 13.2 1.99 40.3 1.76 53.5 1.82 3.12 . .
TOTAL 73.9 1.22 149 1.36 223 1.31 9.39 7.68 0.17
Mineral Resources include Mineral Reserves. There is no certainty that Mineral Resources, not included as Mineral Reserves, will convert to Mineral Reserves
All resources based upon US$1,500/oz gold, US$3.50/lb copper and US$17/oz silver and a 0.72 NZD/USD exchange rate for New Zealand resources.
Open pit resources constrained to shells based upon US$1,500/oz gold except for Waihi open pit resources which are reported within a pit design to the 890mRL.
Waihi: Martha Underground at a 2.15 g/t Au cut-off, WKP at a 2.5 g/t Au cut-off, Correnso at a 2.9 g/t Au cut-off, Martha open pit at a 0.5 g/t Au cut-off and Gladstone open pit at a
0.67 g/t Au cut-off.
Palomino Resources at a 1.5 g/t cut-off and Horseshoe Resources at a 1.44 g/t Au cut-off, the difference due to slightly lower metallurgical recovery at Palomino
For Didipio open pit, only stockpiles remain. Underground resources reported between the 2,460mRL and 1,980mRL with gold equivalence (AuEq) cut-off based on presented gold and
copper prices. AuEq = Au g/t + 1.58 x Cu %. For Didipio UG, all resources proximal to development already planned to access main stoping areas are reported to a lower cut-off of
0.76 g/t AuEq
MEASURED INDICATED MEASURED & INDICATED
Waihi: WKP and Martha Underground resources were publicly released on February 24, 2020 and February 13, 2020 respectively, but are based on drilling and geological information
compiled in 2019.
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See foot notes for Table 2
Figure 3: Changes to Inferred Resources
New Zealand
Waihi
Combined open pit and underground P&P Reserves at Waihi as at December 31, 2019, stood at 0.10 Moz
gold after mine depletion.
Figure 4: Changes to Waihi Proven & Probable Mineral Reserves
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As at December 31, 2019, the Waihi M&I Resources stood at 1.4 Moz gold, representing a year-on-year
increase of 0.6 Moz as drilling at Martha Underground and WKP continued to define and upgrade additional
resources. Refer to news releases related to the Martha Underground and WKP resource updates published
on February 13, 2020 and February 24, 2020, respectively.
Figure 5: Changes to Waihi Measured & Indicated Mineral Resources
The waterfall chart in Figure 5 illustrates an approximate 0. 6 Moz year-on-year increase in Measured and
Indicated Resources, most of which was from upgrading Inferred Resources through infill drilling during 2019.
As at December 31, 2019, the Waihi Inferred Resources stood at 1.3 Moz gold. This represents a 0.3 Moz
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increase at the Martha Underground and WKP projects, net of Inferred Resources that were upgraded to
Indicated during 2019.
Figure 6: Changes to Waihi Inferred Resources
Notwithstanding the current suspension of exploration activities due to the New Zealand Government’s order
to temporarily suspend all “non- essential” business, t he Company expects continued drilling at the Martha
Underground with a focus on resource conversion later in the year. The Company has an additional
exploration target of six to eight million tonnes with grades ranging from four to six grams per tonne within
the Martha Underground p roject. This exploration target is based on the assessment of surface and
underground drilling data collected by the Company in addition to the significant amount of historical and
archived geological and mining data from over a century of mining activity at Waihi. The exploration target is
conceptual in nature and exploration completed on this target to date is not sufficient to define an additional
Mineral Resource above what has been reported. Drilling of this target is expected to continue for the next
several years.
Macraes
As at December 31, 2019, t he P&P Reserves for Macraes stood at 1.1 Moz gold, with 1.0 Moz in the open
pit and 0.06 Moz of gold in the Frasers Underground. Year-on-year drilling-related reserve growth has offset
much of the 2019 mining depletion.
Figure 7: Changes to Macraes Proven & Probable Mineral Reserves
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As at December 31, 2019, the Macraes M&I Resources stood at 3. 5 Moz of gold, including 0.37 Moz in
Frasers Underground. The year-on-year net increase in M&I Resources was due both to drilling-related open
pit resource growth as well as lowered open pit cut -off grade, which was lowered from 0.4 g/t to 0.3 g/t Au,
reflecting low cost stockpile processing scheduled in the latter years of the operation. Reductions (see
adjustments in Figure 8) in Frasers Underground resources reflect the removal of resource in areas deemed
too costly to access.
Figure 8: Changes to Macraes Measured & Indicated Mineral Resources
As at December 31, 2019, Macraes Inferred Resources stood at 0.9 Moz of gold, an increase from the
previous year, due mainly to lowered cut -off grade which was partially offset by mining depletion and
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upgrading of Inferred Resources to the Indicated category. The Company will continue to drill multiple targets
along the Hyde-Macraes Shear Zone with a focus on Golden Point Underground.
Figure 9: Changes to Macraes Inferred Resources
Reefton
In December 2016, the Company announced the closure of the Reefton Mine and as a result, associated
resources were removed from the Company’s inventory.
Resources for the nearby Blackwater Project remain on the Company’s inventory and remain unchanged
from EOY 2018 reported resources.
United States
Haile
P&P Reserves total led 2.9 Moz of gold including 0.44 Moz of gold in the Horseshoe Underground. Total
Mineral Reserves have reduced by 0.17 Moz net of resource growth, due to open pit mining depletion and to
a lesser extent, application of TSF construction costs. The open pit cut -off grade has increased to 0.5 g/t
from 0.45 g/t Au and resulted in a small reduction in the size of the reserve pit design.
Figure 10: Changes to Haile Proven & Probable Mineral Reserves