Ero Copper intercepts 67.0 meters grading 9.21% copper including 21.0 meters grading 14.14% copper in Deepening Extension of the Pilar Mine, and at NX Gold, intercepts 9.0 meters grading 22.66 gpt gold, the best hole drilled in the history of the mine
Ero Copper Corp. (the "Company") (TSX: ERO, NYSE: ERO) is pleased to provide a quarterly update on the ongoing exploration drill programs for its 99.6% owned MCSA Mining Complex located in Bahia State, Brazil and its 97.6% owned NX Gold Mine located in Mato Grosso State, Brazil. This update encompasses drill and assay results received from early April through mid-June 2021.
MCSA In-Mine and Near-Mine Exploration Programs
NX Gold Mine Highlights
MCSA Past Producing Open Pit Mine Re-Evaluation
MCSA Platinum Group Metal Evaluation
Results from the Company's PGM evaluation program continues to highlight the persistent presence of gold and platinum group elements ("PGEs") throughout the deposits of the Curaca Valley, including within the newly identified high-grade lenses of the Deepening Extension at the Pilar Mine, as well as zones of enriched PGEs associated with low-grade near-surface copper lenses at the Surubim Mine. Results are highlighted by:
Commenting on the results, David Strang, CEO, stated, "I believe our exploration results this quarter, in the simplest sense, serve to highlight what a special asset the Curaca Valley really is. On a grade-meter basis, the holes we have drilled in the Deepening Extension of the Pilar Mine are not only some of the best intercepts we have ever drilled as a Company, but rank favorably amongst all copper exploration drilling globally over the last few years. The new Deepening Extension holes, drilled over 350 meters in strike length at the limit of known mineralization of the mine, provide strong support for the decision we made last year to invest in the long-term future of the Pilar Mine with a new external shaft. On the back of these drill results, and in parallel with detailed engineering work currently underway for the Deepening Extension Project, we are advancing new studies aimed at potentially unlocking additional value from the Deepening Extension zone of the Pilar Mine. Throughout the broader Curaca Valley, we continue to advance all exploration objectives within our portfolio, highlighting potential to augment our operations over the near, medium and longer term as we continue to work towards increasing production versus what is outlined in our 2020 life-of-mine plan through utilization of available excess mill capacity.
We are also excited by the step-out drilling at Lagoa da Mina beneath the past producing Angicos Mine and new drilling beneath the Surubim Mine, as both programs continue to highlight continuity within high-grade mineralized lenses that remain open to depth. On the regional side, we are continuing to work and refine exploration targets within previously announced mineral systems and have progressed work within several new areas we expect to provide more color on during the second half of the year. In addition, now that multi-element analysis has been brought in-house, we have been able to clear a backlog of pending assay results from the Deepening, provide color on our review of the Surubim Mine historic data and present results from new drilling in the Deepening Extension. Overall, these results continue to support our hypothesis that PGMs (and gold) are prevalent throughout the Curaca Valley, and we will continue to allocate resources to this program.
At NX Gold, where we currently have nine drill rigs operating, exploration continues to focus on extending the known mineralization of the Santo Antonio Vein, identifying new veins within and adjacent to the mine's infrastructure, such as the Matinha Vein, and conducting the first regional exploration drill program on newly identified structures. While assay results from these ongoing programs have been slow to return due to a back-log stemming from lab closures, due to Covid-19 in Brazil and Peru, we are extremely pleased by the early results of these programs and the continued success in extending the Santa Antonio Vein. In addition to intercepting the best hole ever drilled at the NX Gold Mine in step-out drilling within the Santo Antonio Vein and discovery of high-grade extensions of the Matinha Vein at depth, we have also discovered near-surface gold mineralization on two completely new gold systems, located 1.2 and 25 kilometers away from the NX Gold Mine, respectively. Work to further identify and extend mineralization within these newly discovered systems remains ongoing."
There are currently twenty-four drill rigs working throughout the Curaca Valley, including six drill rigs allocated to regional exploration. Nine drill rigs are operating at NX Gold and the Company now has three drill rigs operating at the Boa Esperanca project in Para State.
Exploration activities during the period continued to advance target zones and new mineral systems within each of the Company's core exploration programs. These programs are focused on developing a portfolio of assets in parallel with potential to meaningfully augment each phase of the Company's life-of-mine production plans from the near to medium-term and over the long-term at both the MCSA Mining Complex and the NX Gold Mine. A summary of relevant highlights from these programs is presented in Table 1, attached to this press release.
Expansions and extensions, as referenced herein, reflect mineralization not captured in the Company's updated NI 43-101 (as defined below) compliant mineral resource and mineral reserve models, as outlined in the Company's technical reports dated January 8, 2021, and January 14, 2021 for NX Gold Mine and the MCSA Mining Complex (or the "Curaca Valley"), respectively. There has been insufficient work and analysis surrounding new discoveries, as referenced herein, to define a mineral resource and it is uncertain if further exploration and analysis will result in such targets being delineated as a mineral resource.
The drill holes outlined in this press release within the Pilar and Vermelhos Districts will be made available on the Company's Curaca Valley site tour and interactive three-dimensional models for the Pilar Mine and the Vermelhos System, which can be accessed via the Company's website (www.erocopper.com) or via VRIFY Technology Inc. ("VRIFY") (www.vrify.com).
IN-MINE & NEAR-MINE EXPLORATION PROGRAMS
During the period, the Company continued to prioritize drilling of the Deepening Extension within the Pilar Mine, where the Company continues to confirm thick and high-grade mineralization at depth as well as extensions of the Vermelhos Mine, including within the Southern Vermelhos Corridor.
The Deepening Extension Zone, Pilar Mine
Exploration activities in the Deepening Extension remain focused on upgrading the Inferred mineral resource classification through infill drilling and further extending the known limits of mineralization to depth. The drill program, using directional drilling technology to evaluate the mineralized potential of the Deepening Extension to depth, continues as planned. These holes can be differentiated by the letter ascribed to the same numerical "parent" hole. Deepening Extension drilling is currently targeting mineralization on the East Limb of the Pilar Mine to level -1550 approximately 1,200 meters to 2,000 meters below surface (completed to level -1,000).
The known limits of mineralization within the Deepening Extension, which remains open, extends over approximately 900 meters in strike length, over a total down-dip depth of approximately 600 meters and over average thicknesses ranging from 10 to 15 meters with localized thickening throughout the zone. Within the total strike length, the Company had previously identified two higher-grade continuous zones of sub-vertical mineralization within the northern and south-central segments of the target area, and a new offset zone of parallel mineralization located approximately 70 to 120 meters east of the Deepening Extension, known as the "Offset Zone" (first detailed in the Company's press release dated December 15, 2020).
At the deepest limits of the 2020 Inferred mineral resource shell, new drilling has highlighted a continuous zone of extremely high-grade "Superpod" style mineralization where the two plunging zones previously identified within the northern and south-central segments appear to be joining together over an identified strike length of approximately 350 meters. Drilling in this area has returned some of the best drill results by the Company in the Curaca Valley to date. The new zone remains open and is approximately 470 meters below the current infrastructure of the mine. Results along the 350 meter strike length are located at the same level as the previously announced deepest known intercepts of the Pilar Mine and Curaca Valley (FC48173A and FC48173B) and indicate the potential for increased thickening, of mineralization, to depth within the mine. Apparent thickening within the zone exceeds 30 meters compared to previously modeled thicknesses of between 10 to 15 meters within the 2020 Inferred mineral resource shell. Results are highlighted on section 55 by hole FC5522 that intercepted 67.0 meters grading 9.21% copper including 21.0 meters grading 14.14% copper, and at the same level, on section 53 and 48, approximately 200 and 350 meters south of the intercept in hole FC5522, respectively: hole FC5389 that intercepted 46.6 meters at 4.98% copper, including 31.2 meters at 6.94% copper, and hole FC48173E that intercepted 72.1 meters at 2.81% copper including 14.0 meters at 4.40% copper. These new intercepts, on section 48 to the south, are located approximately 160 meters below hole FC48183A that intercepted 32.8 meters grading 5.75% copper, including 10.4 meters grading 8.97% copper and, to the north on section 56, 170 meters below the previously announced intercept of hole FC5625 that intercepted 96.4 meters grading 3.97% copper including 60.6 meters grading 5.61% copper. Together with prior results, these intercepts demonstrate vertical continuity of high-grade mineralization over a down-dip distance of approximately 200 meters throughout the 350 meters of identified strike length. Please refer to the Company's press release dated April 29, 2021, June 23, 2020, and December 15, 2020 for additional detail on previously released holes.
New multi-element results from the Deepening Extension have been made available through a combination of clearing backlogged results from previously announced holes in the Company's December 2020 and April 2021 exploration press releases previously delayed in South Africa, as well as new results from the Company's in-house multi-element analysis program. Overall, the results of this program continue to highlight persistent values of elevated PGMs throughout zones of copper mineralization as well as outside of the primary mineralized lenses. Results are highlighted by hole FC5389 that intercepted a 1.0 meter zone of enriched PGMs grading 0.35% Cu and 6.44 gpt 3PGE+Au (0.10 gpt Au, 1.46 gpt Pd, 4.28 gpt Pt, 0.70 gpt Rh). The enriched PGM mineralization identified in hole FC5389 lies approximately 23 meters downhole from the high-grade copper mineralization intercepted in the same hole (46.6 meters grading 4.98% copper including 31.2 meters grading 6.94% copper). As noted previously, the copper values within this PGM enriched zone are below cut-off grades, and as a result, historically this zone would have been treated as waste. Additional work to isolate and model zones of enriched PGMs going forward, such as those demonstrated in hole FC5389, remains ongoing.
Please see Figure 1 for a north-south long section, Figure 2 for a west to east composite section and Figure 3 for a level map showing collar locations of Deepening Extension drilling within the Pilar Mine.
Hole ID From To Length Cu Ni Au Pd Pt Rh 3PGE+ (m) (m) (m) (%) (%) (gpt) (gpt) (gpt) (gpt) Au (gpt) Q2 2021 Deepening Intercepts (including available PGM Results) FC48173E 316.8 323.1 6.3 2.10 0.02 0.09 NA 0.03 NA 0.13 and 329.4 336.0 6.7 1.06 0.02 0.03 NA 0.02 NA 0.05 and 343.0 346.0 3.0 7.23 0.07 0.02 0.08 0.02 NA 0.13 and 392.0 397.0 5.0 1.27 0.02 0.03 NA NA NA 0.03 and 406.0 478.2 72.1 2.81 0.03 0.11 0.04 0.06 0.01 0.21 including 429.0 443.0 14.0 4.40 0.03 0.11 0.02 0.04 0.01 0.18 FC48183A 465.2 498.0 32.8 5.75 0.06 Assay Results Pending including 468.2 478.6 10.4 8.97 0.06 Assay Results Pending FC5389 794.3 800.3 6.0 2.19 0.03 0.10 NA 0.04 NA 0.14 and 811.3 857.9 46.6 4.98 0.04 0.10 0.07 0.13 0.01 0.30 including 824.8 855.9 31.2 6.94 0.04 0.10 0.08 0.07 0.01 0.13 and 879.9 880.9 1.0 0.35 0.02 0.10 1.46 4.28 0.70 6.44 and 887.9 894.9 7.0 2.25 0.03 Assay Results Pending FC5395 744.3 782.4 38.1 3.60 0.06 Assay Results Pending including 767.3 777.4 10.1 5.19 0.08 Assay Results Pending FC5520 NSI NSI NSI NSI NSI NSI NSI NSI NSI NSI FC5521 887.5 893.5 6.0 1.77 0.02 0.03 0.07 0.44 0.01 0.54 and 911.4 916.9 5.5 3.00 0.03 Assay Results Pending FC5522 774.7 841.7 67.0 9.21 0.03 0.14 0.10 0.09 NA 0.32 including 795.7 816.7 21.0 14.14 0.03 0.20 0.14 0.08 NA 0.42 and 871.6 878.6 7.0 1.93 0.01 0.07 0.00 0.03 NA 0.11 FC5523 801.9 837.0 35.2 5.51 0.06 0.09 0.06 0.08 NA 0.23 including 820.9 829.9 9.0 8.60 0.07 0.08 0.09 0.09 NA 0.26 Previously Announced Deepening Intercepts with Completed PGM Analysis (December 2020 and April 2021) FC45194 177.5 180.5 3.0 4.48 0.03 0.06 0.19 NA NA 0.25 FC47173 647.8 657.8 10.0 0.87 0.07 0.05 0.02 0.01 NA 0.08 and 665.8 670.8 5.0 0.83 0.06 0.06 0.03 0.05 NA 0.14 and 679.8 682.8 3.0 0.81 0.08 0.06 0.02 0.02 0.01 0.12 and 812.5 819.7 7.2 3.28 0.04 0.25 0.07 0.01 NA 0.34 including 814.5 817.5 3.0 4.35 0.04 0.17 0.11 0.02 NA 0.30 FC48142 699.9 703.9 4.0 1.11 0.01 0.05 NA NA NA 0.05 and 727.4 748.3 20.9 5.16 0.04 0.09 0.08 0.01 NA 0.18 including 727.4 732.9 5.4 5.16 0.04 0.08 0.17 0.02 NA 0.27 also including 738.9 741.9 3.0 10.02 0.05 0.23 0.08 NA NA 0.31 FC48155 617.9 664.5 46.5 4.96 0.04 0.18 0.11 0.04 NA 0.33 including 621.0 657.5 36.5 6.08 0.05 0.21 0.14 0.05 NA 0.39 also including 641.5 647.5 6.0 11.98 0.08 0.09 0.31 0.03 NA 0.43 FC5381 509.3 516.5 7.2 3.28 0.02 0.13 0.04 0.02 NA 0.18 including 510.3 512.5 2.2 8.03 0.05 0.24 0.10 0.03 NA 0.38 and 526.4 529.6 3.2 5.64 0.03 0.05 0.13 0.02 NA 0.20 and 612.8 616.8 4.1 1.06 0.01 NSI NSI NSI NSI 0.00 and 622.1 625.2 3.1 1.63 0.03 0.03 0.02 0.02 NA 0.07 and 682.9 688.9 6.0 1.07 0.03 0.07 0.02 NA NA 0.09 FC5515 NSI NSI NSI NSI NSI NSI NSI NSI NSI NSI FC5516 512.6 519.9 7.3 1.69 0.03 0.12 0.08 NA NA 0.20
Vermelhos Mine Extensions
Within the Vermelhos Mine, drilling continued to test continuity of mineralization near existing mine infrastructure and target new high-grade lenses at depth. Results are highlighted by new drilling that sought to test lateral continuity east of the previously announced "Novo Zone" discovery. The Novo Zone is located approximately 200 meters below the existing infrastructure of the Vermelhos Mine and has been interpreted as a sub-horizontal, north-plunging lens of high-grade massive sulphide mineralization, extending over an identified strike length to date of approximately 200 meters. Results from this ongoing program continue to indicate that the zone remains open, highlighted by hole FVS-870 that intercepted 3.9 meters grading 1.13% copper and hole FVS-873 that intercepted 4.1 meters grading 0.91% copper, drilled approximately 50 meters and 150 meters east, respectively, of previously announced hole FVS-922 (13.8 meters grading 2.62% copper including 4.0 meters grading 5.52% copper). Additional extensional drilling remains ongoing. Please refer to the Company's press release dated April 29, 2021 for previously released holes.
Adjacent to existing mine infrastructure, mineralization continues to extend beyond the previously modeled limits of the deposit through ongoing infill drilling. Results are highlighted by hole FVS-999 that intercepted 27.0 meters grading 6.86% copper including 3.8 meters grading 16.29% copper at the eastern edge of the Toboggan orebody, indicating significant thickening within an area previously modeled as narrow lenses. In addition, two holes drilled for mine planning purposes were extended to depth beneath Toboggan, and the installed infrastructure of the mine, the results of which continue to provide evidence of high-grade mineralization continuing to depth. Results of this drilling are highlighted by FVS-1234 that intercepted 6.7 meters grading 6.80% copper including 2.0 meters grading 9.03% copper immediately beneath the Toboggan orebody and hole FVS-1253 that intercepted 5.7 meters grading 3.38% copper approximately 125 meters beneath the Toboggan orebody. Mineralization within the Vermelhos Mine remains open down-plunge and drilling of the new target zones, along with borehole electro-magnetic ("EM") surveys, remains ongoing.
Please see Figure 4 for a plan map detailing all Vermelhos near-mine collar locations, Figure 5 for north-south long section detailing all Vermelhos near-mine drilling.
Hole ID From (m) To (m) Length (m) Cu (%) Vermelhos Mine Toboggan Extension FVS-988* 21.6 25.3 3.8 6.07 and 31.6 37.2 5.6 11.86 including 33.6 35.6 2.0 15.72 FVS-997* 11.5 18.2 6.7 6.28 FVS-999* 50.7 77.7 27.0 6.86 including 73.4 77.2 3.8 16.29 FVS-1063* 7.0 13.2 6.2 9.81 including 7.0 10.3 3.3 15.48 FVS-1068* 24.8 32.2 7.4 2.19 FVS-1124* 10.8 17.2 6.5 2.43 including 11.8 13.8 2.0 5.12 FVS-1198* 26.9 31.8 4.9 3.06 and 66.9 72.5 5.6 1.03 FVS-1234* 0.0 6.7 6.7 6.80 including 2.0 4.0 2.0 9.03 FVS-1253* 5.9 9.7 3.8 8.15 including 5.9 7.9 2.0 12.90 and 166.5 172.2 5.7 3.38 FVS-1255* 1.6 5.5 3.9 11.17 Novo Zone FVS-870 174.8 178.7 3.9 1.13 FVS-873 131.5 135.6 4.1 0.91 FVS-874 NSI NSI NSI NSI FVS-926 573.7 576.7 3.0 2.03 FVS-927 NSI NSI NSI NSI FVS-928 NSI NSI NSI NSI
Southern Vermelhos Corridor
Exploration activities within the Southern Vermelhos Corridor, a near-mine exploration zone extending from the Siriema Deposit to the UG1 mining area of the Vermelhos Mine, remain focused on two primary objectives: (i) testing continuity of high-grade copper mineralization within the corridor, and (ii) conducting borehole EM surveys to identify high-grade exploration targets. The target zone within the Southern Vermelhos Corridor has a north-south strike length of approximately 700 meters, an east-west section width of approximately 300 meters and is currently defined to a depth of approximately 800 meters below surface.
The program continues to demonstrate the presence of multiple stacked mineralized lenses, including high-grade mineralization. Three drill rigs will continue to remain operational within the Southern Vermelhos Corridor to systematically test continuity of mineralization. The program has been designed on 50 meter drill spacing. The focus will continue to be the northern section of the Southern Vermelhos Corridor given its proximity to the existing Vermelhos Mine infrastructure and the potential for exploration success to meaningfully enhance the near-term base-case production profile and extend the overall mine life of the mine.
Results are highlighted by hole FSI-108 that intersected 20.0 meters grading 0.97% copper and 5.6 meters grading 2.09% copper as well as hole FSI-109 that intersected 18.9 meters grading 1.35% copper including 4.0 meters grading 3.73% copper. These intercepts are interpreted to be part of the down-plunge continuity of high-grade mineralization extending from surface at the Siriema deposit to depth. To date, this north-plunging zone has been traced over a total down-plunge length of 1,100 meters from surface to the intercepts of FSI-108 and FSI-109, which are the deepest mineralized intercepts drilled within the Vermelhos System to date. Results indicate the presence of high-grade copper mineralization up to 800 meters below surface and the mineralization remains open.
Intercepts below three meters in thickness drilled within the Southern Vermelhos Corridor are reported below as not significant, consistent with the Company's minimum mining thickness and overall approach to reporting exploration drill results.
Please see Figure 4 for a plan map detailing Southern Vermelhos Corridor collar locations and Figure 5 for a north-south long section detailing all Vermelhos near-mine drilling.
Hole ID From (m) To (m) Length (m) Cu (%) Southern Vermelhos Corridor FSI-108 853.3 873.3 20.0 0.97 and 896.5 902.1 5.6 2.09 FSI-109 900.7 919.6 18.9 1.35 including 900.7 904.7 4.0 3.73 FVS-918 562.6 567.9 5.2 0.78 FVS-920 627.8 631.7 3.9 0.79 FVS-921 612.2 618.5 6.4 0.72 FVS-923 NSI NSI NSI NSI
PAST PRODUCING MINE RE-EVALUATION
In late 2020, the Company commenced an exploration program designed to strategically review and re-evaluate known zones of mineralization existing beneath several past producing open pit mines throughout the Curaca Valley. This program sought to utilize and incorporate new datasets developed during the Company's regional exploration programs to isolate and extend high-grade mineralized envelopes beneath the mines that may be suitable for open pit and/or underground mine development. The results from this program continue to demonstrate continuity of high-grade mineralization, and with future success, these new zones may form an integral component of the Company's near to medium-term growth objectives with respect to utilizing excess mill capacity at elevated grade profiles.
Lagoa da Mina, Angicos Mine & Surubim Mine, Surubim District
The past producing open pit Angicos Mine, within the Surubim District, is located approximately 11 kilometers northeast of the Surubim Open Pit Mine and approximately 32 kilometers north of the Pilar Mine. While the aggregate mineral resource of the Angicos Mine is considered to be primarily lower-grade disseminated copper sulphide mineralization, the Company has identified a high-grade zone within the overall mineralized envelope of the mineral resource that remains open along strike and to depth. To date, an interpreted south-plunging high-grade lens dipping to the west at approximately 60 degrees, can be traced over 150 meters in strike length, 100 meters down-dip and over variable thickness of between 30 and 45 meters.
Results at Lagoa da Mina continue to highlight continuity of high-grade mineralization and further extend the known limits of high-grade mineralization within the zone. Results are highlighted by hole FLM-77 that intercepted 32.2 meters grading 2.69% copper including 6.0 meters grading 4.00% copper. This new intercept was drilled as a 30 meter step-out hole from previously announced hole FLM-16 that intercepted 15.0 meters grading 3.03% copper including 4.0 meters grading 4.44% copper. At the Surubim Mine, results are highlighted by new drilling, located approximately 150 meters beneath the bottom of the open pit, by hole FS-GH007 that intercepted 7.2 meters grading 2.01% copper including 3.0 meters grading 3.07% copper. The new drill result beneath the Surubim Mine is located approximately 275 meters south from previously released hole FSEX-64 that intercepted 9.1 meters grading 1.92% Cu including 5.1 meters grading 3.05% Cu. Please refer to the Company's press releases dated April 29, 2021, and September 25, 2018 for complete Lagoa da Mina and Surubim Mine results, respectively.
Please see Figure 6 for a plan map detailing Lago da Mina collar locations and Figure 7 for a west-east cross-section, as well as Figure 8 for a plan map detailing Surubim collar locations and Figure 9 for a north-south long section of the Surubim Mine.
Hole ID From (m) To (m) Length (m) Cu (%) Lagoa da Mina FLM-77 216.6 248.8 32.2 2.69 including 235.3 241.3 6.0 4.00 FLM-78 216.9 243.4 26.5 0.90 FLM-79 192.0 209.5 17.5 0.65 FLM-80 NSI NSI NSI NSI FLM-81 288.1 303.3 15.3 0.79 including 288.1 293.3 5.3 1.42 FLM-82 264.3 283.3 19.0 1.18 and 298.1 332.0 33.9 0.75 Surubim FS-GH007 356.0 363.2 7.2 2.01 including 357.0 360.0 3.0 3.07
CURACA VALLEY DISTRICT PGM REVIEW
Following the Company's press release dated December 15, 2020, demonstrating evidence of background and elevated PGM concentrations throughout the deposits of the Curaca Valley, the Company embarked on a program to re-analyze historic drill data for PGMs in the Deepening Extension of the Pilar Mine and the Surubim Mine through a comprehensive testing program with contracted laboratories in South Africa. As a result of delays in receiving assay results due to COVID-19 laboratory closures and the favorable PGM results obtained in 2020, the Company installed and commissioned its own internal multi-element analysis capabilities in early 2021 for all of its ongoing drill programs. During the period, the Company used its own laboratory to expedite analysis of drill results from the Deepening Extension and the Surubim Mine. PGM analysis for previously drilled holes within the Deepening Extension was conducted through laboratories in South Africa and, for new holes drilled during Q2 2021, the Company utilized its own laboratory. Please refer to the Deepening Extension section of this press release for additional PGM analysis results.
The PGM analysis program at the Surubim Mine sought to test intervals both within and immediately adjacent to known lenses of copper mineralization at the southern end of the deposit. Results from the program are highlighted by hole FS-GH006 that intercepted 16.5 meters grading 1.27% Cu, 0.09% Ni and 0.52 gpt 3PGE+Au (0.38 gpt Au, 0.11 gpt Pd and 0.04 gpt Pt). Within this intercept, two distinct zones of mineralization occur: (i) a "PGM" rich zone of 3.0 meters grading 2.86% copper, 0.13% nickel and 0.62 gpt 3PGE+Au (0.34 gpt Au, 0.23 gpt Pd, and 0.04 gpt Pt), and (ii) an "Au rich" zone of 3.5 meters grading 2.39% copper, 0.04% nickel and 1.00 gpt 3PGE+Au (0.92 gpt Au, 0.05 gpt Pd and 0.03 gpt Pt). Rh values for the Surubim PGM analysis program were below detection limits.
Please see Figure 8 for a plan map detailing Surubim collar locations and Figure 9 for a north-south long section of the Surubim Mine including PGM results.
Hole ID From To Length Cu Ni Au Pd Pt Rh 3PGE+ (m) (m) (m) (%) (%) (gpt) (gpt) (gpt) (gpt) Au (gpt) Surubim Open Pit Mine, PGM Analysis (previously drilled holes) FS-C003 103.0 170.0 67.0 0.90 0.02 0.09 0.02 0.03 NA 0.14 including 107.0 114.0 7.0 1.68 0.04 0.14 0.03 0.02 NA 0.18 also including 125.0 140.0 15.0 0.84 0.02 0.20 0.01 0.05 NA 0.26 FS-D006 164.8 180.2 15.5 0.50 0.02 0.04 0.02 0.04 NA 0.10 and 186.0 197.0 11.0 0.47 0.02 0.03 NA NA NA 0.03 and 207.2 227.4 20.3 1.45 0.05 0.17 0.05 0.02 NA 0.24 including 216.6 219.6 3.0 3.02 0.09 0.27 0.12 0.03 NA 0.41 FS-F003 64.0 67.0 3.0 NA NA NA 0.00 0.22 NA 0.22 and 147.0 159.0 12.0 1.38 0.03 0.11 0.04 0.06 NA 0.20 including 155.0 158.0 3.0 1.77 0.03 0.17 0.03 0.04 NA 0.24 and 220.0 223.0 3.0 0.06 0.01 NA 0.02 0.12 NA 0.14 FS-GH006 191.2 207.7 16.5 1.27 0.09 0.38 0.11 0.04 NA 0.52 including 192.2 195.2 3.0 2.86 0.13 0.34 0.23 0.04 NA 0.62 (PGM rich) also including 204.1 207.7 3.5 2.39 0.04 0.92 0.05 0.03 NA 1.00 (Au rich)
NX GOLD MINE
The NX Gold Mine is a producing high-grade gold mine, located in Mato Grosso State, Brazil. Beginning in late 2018, a comprehensive in-mine exploration program commenced for the first time since the mine was commissioned in 2012 resulting in the Santo Antonio Vein discovery. In late 2019, all mining activity was transitioned from the Bras and Buracão Veins into the central Santo Antonio Vein. To date, the Santo Antonio Vein has been defined over a lateral extent of approximately 400 meters, a down-plunge distance of approximately 400 meters and the vein remains open to depth (see press release dated April 18, 2019 for detail regarding the Santo Antonio Vein discovery).
Drilling at the NX Gold Mine remains focused on three primary objectives for 2021: (i) infill and extension of the Santo Antonio Vein, (ii) delineation and discovery of new gold-bearing veins within the NX Gold Mine system near existing infrastructure, such as the Matinha Vein, and (iii) executing upon the first regional exploration program conducted on the broader NX Gold land package.
NX Gold In-Mine Programs
Within the NX Gold Mine system, drilling was focused on testing down-plunge continuity of the Santo Antonio Vein and evaluating the potential for new down-plunge vein extensions within a previously identified vein, known as Matinha, located approximately 550 meters east of development within the Bras Vein (approximately 750 meters east of development within the Santo Antonio Vein).
Results are highlighted by Santo Antonio down-plunge drilling in hole SA94A that intercepted 9.0 meters grading 22.66 gpt gold making it the best hole drilled by the Company on a grade-meter basis in the history of the NX Gold Mine and the deepest hole drilled in Santo Antonio to date. The intercept is located approximately 10 meters beyond the previously defined limit of the 2020 Inferred mineral resource shell of the Santo Antonio Vein and approximately 45 meters down-plunge of previously announced hole SA89 that intercepted 2.7 meters grading 15.38 gpt gold. As a result of this new intercept and the apparent thickening of the Santo Antonio Vein to depth, an exploration drift into the hanging wall has commenced development to allow for expedited detailed drilling from underground in the immediate area of this intercept.
In addition to positive developments from the Santo Antonio Vein, the first drill program designed to test the down-plunge continuity of the Matinha Vein at depth was undertaken during the first half of 2021. Results from this program are highlighted by hole MAT20A that intercepted 2.8 meters grading 19.73 gpt gold approximately 550 meters east of the existing infrastructure of the Bras Vein. The intercept of MAT20A is located approximately 480 meters below surface, and approximately 600 meters down plunge from the previously known limit of the Matinha Vein. This newly discovered extension at depth is analogous to the first discovery hole from the Santo Antonio Vein exploration program in 2019 (hole SA01 that intercepted 2.2 meters grading 14.10 gpt Au). Step-out drilling is underway in the vicinity of MAT20A to define structural controls within the newly discovered Matinha Vein extension, which remains open along strike and to depth.
Please see Figure 10 for a plan map detailing NX Gold Mine collar locations and Figure 11 for an east-west composite section.
Hole ID From (m) To (m) Length (m) Au (gpt) Santo Antonio Extension to Depth SA94 770.8 773.5 2.7 1.51 including 772.1 772.6 0.5 4.31 SA94A 771.3 780.3 9.0 22.66 Matinha Vein MAT14 390.67 392.9 NSI NSI MAT15 433.83 435.00 1.17 2.30 including 434.42 435.00 0.6 4.20 MAT16 419 419.33 NSI NSI MAT17 NSI NSI NSI NSI MAT18 633.15 634.15 1.0 3.54 MAT19 606.07 606.35 0.5 1.93 MAT20 688.13 689.13 1.0 2.68 MAT20A 524.88 527.69 2.8 19.73 MAT21 NSI NSI NSI NSI MAT23 NSI NSI NSI NSI
NX Gold Regional Exploration Program
The first regional exploration campaign on the broader NX Gold land package commenced in early 2021. Results from this program, to date, have demonstrated that additional gold-bearing quartz veins are prevalent throughout the broader NX Gold District. Work is currently focused within the Cobra System, located approximately 1.2 kilometers north of the NX Gold Mine, and the Mata Verde System, located approximately 25 kilometers north-north-east of the NX Gold Mine. To date, the Cobra System has been traced over approximately 5 kilometers and tested with shallow drilling over a limited 140 meters of strike length. Similarly, the Mata Verde System has been traced over approximately 10.5 kilometers, of which, only about 1.1 kilometers has been tested with shallow drilling to date. Results, while preliminary, are encouraging and are highlighted by hole MTV10 that intercepted a high-grade quartz vein grading 20.20 gpt gold. Ongoing work streams within these systems includes geochemical surveys, geophysical surveys, and follow-up drilling. Exploration drilling of other identified priority regional exploration target systems is planned for the second half of 2021.
Please see Figure 12 for a plan map detailing NX Gold Mine regional program collar locations.
Hole ID From (m) To (m) Length (m) Au (gpt) Sovaco de Cobra ("Cobra") System SC01 19.0 20.0 1.0 6.23 and 38.6 39.0 0.4 2.55 SC02 NSI NSI NSI NSI Mata Verde System MTV01-MTV09 NSI NSI NSI NSI (early exploration) MTV10 231.7 232.2 0.5 20.20 MTV11 NSI NSI NSI NSI MTV12 NSI NSI NSI NSI MTV13 NSI NSI NSI NSI MTV14 NSI NSI NSI NSI MTV15 NSI NSI NSI NSI MTV16 52.0 54.0 2.0 1.60 MTV17 NSI NSI NSI NSI MTV18 NSI NSI NSI NSI
NOTE ON NI 43-101 COMPLIANT TECHNICAL REPORT(S)
The conversion of drill results presented in this press release into NI 43-101 compliant mineral resources and mineral reserves, including but not limited to the drill results associated with the new and potential extensions of mineralization across each of the mineral districts, including new discoveries and newly identified mineralized systems outlined in this press release, all require additional work and analysis that remains ongoing. To date, there has been insufficient exploration and accompanying analysis to define a mineral resource and it is uncertain if further exploration will result in these extensions being delineated as a mineral resource. Accordingly, the results herein may not be included in future NI 43-101 compliant mineral resources or mineral reserves depending on the results of this additional work and analysis, and other technical and/or economic reasons.
QUALITY ASSURANCE / QUALITY CONTROL
MCSA Mining Complex
The Company is currently drilling on surface and underground with core drill rigs using a combination of owned and third-party contracted drill rigs. During the period from April 2021 through June 2021, third-party drill rigs were operated by Major Drilling do Brasil Ltda., Tamarama Sondagens Ltda., Layne Christensen Co., and DrillGeo Geologia e Sondagem Ltda., all of whom are independent of the Company. Drill core is logged, photographed and split in half using a diamond core saw at the secure core logging and storage facilities of Mineracão Caraiba S.A. ("MCSA"). Half of the drill core is retained on site and the other half core is used for analysis, with samples collected on one-meter sample intervals unless an interval crosses a geological contact. Reverse circulation cuttings are split at the drill rig using one-meter sample intervals. All sample preparation is performed in MCSA's secure on-site laboratory. Total copper is determined using a nitric-hydrochloric acid digestion and Atomic Absorption Spectrometry ("AAS") and/or Titration. Oxide copper values are determined using sulfuric acid digestion followed by AAS. PGM and gold analysis during the period was performed at the SGS S.A.'s facility in Rustenburg, South Africa and at MCSA's secure on-site laboratory with values determined using nickel sulphide and lead collection fire assay and Inductively Coupled Plasma - Optical Emission Spectrometry. SGS S.A. is independent of the Company. All sample results during the period have been monitored through a QA/QC program that includes the insertion of certified standards, blanks, and pulp and reject duplicate samples. Regular check-assays are submitted to ALS Brasil Ltda's facility located in Vespasiano, Minas Gerais, Brazil, at a rate of approximately 5%. ALS Brasil Ltda is a subsidiary of ALS Limited and is independent of the Company.
NX Gold Mine
The Company is currently drilling on surface with third-party contracted core drill rigs. During the period from April 2021 through June 2021 third-party drill rigs were operated by Servitec Foraco Sondagem S.A. who is independent of the Company. Drill core is logged, photographed and split in half using a diamond core saw at NX Gold S.A.'s ("NX Gold") secure core logging and storage facilities. Half of the drill core is retained on site and the other half core is used for analysis, with samples collected on half-meter sample intervals for quartz vein and one-meter intervals in surrounding rock unless such interval crosses a geological contact. Samples are sent to ALS Brasil Ltda.'s laboratory in Goiania (Brazil) for preparation and are analyzed by the certified laboratory of ALS Peru S.A., whom are independent of the Company. During the period, gold content has been determined by both fire assay and screen fire assay. All sample results during the period have been monitored through a QA/QC program that includes the insertion of certified standards, blanks, and pulp and reject duplicate samples at a rate of one standard, one blank, and one duplicate pulp sample per every 20 samples for a blended rate of approximately 5%.
Emerson Ricardo Re, MSc, MBA, MAusIMM (CP) (No. 305892), Registered Member (No. 0138) (Chilean Mining Commission) and Resource Manager of the Company who is a "qualified person" within the meanings of NI 43-101, has reviewed and approved the disclosure of technical information, including verification of the sampling, analytical and testing data in this press release. Quarterly reviews entail sampling and laboratory procedure review as well as verification of original assay certificates associated with a selection of samples from Company's internal database included in this press release.
ABOUT ERO COPPER CORP
Ero, headquartered in Vancouver, B.C., is focused on copper production growth from the MCSA Mining Complex, located in Bahia, Brazil. The Company's primary asset is a 99.6% interest in the Brazilian copper mining company, MCSA, 100% owner of the MCSA Mining Complex with over 40 years of operating history in the region. The Company currently mines copper ore from the Pilar and Vermelhos underground mines. In addition to the MCSA Mining Complex, MCSA owns 100% of the Boa Esperanca development project, an IOCG-type copper project located in Para, Brazil and the Company owns 97.6% of the NX Gold Mine, an operating gold and silver mine located in Mato Grosso, Brazil. Additional information on the Company and its operations, including technical reports on the MCSA Mining Complex, Boa Esperanca and NX Gold properties, can be found on the Company's website (www.erocopper.com), on SEDAR (www.sedar.com) and EDGAR (www.sec.gov).
ERO COPPER CORP. Signed: "David Strang" For further information contact: David Strang, CEO Courtney Lynn, VP, Corporate Development & Investor Relations (604) 335-7504 firstname.lastname@example.org
Figures accompanying this release can be downloaded here: