Ero Copper intersects 31.8 meters grading 2.22% copper including 5.0 meters grading 5.56% copper at the recently announced Siriema Discovery

VANCOUVER, Sept. 12, 2019 - Ero Copper Corp. (the “Company”) (TSX: ERO) is pleased to provide a quarterly update on the ongoing exploration drill programs on its 99.6% owned Vale do Curaçá Property located in Bahia State, Brazil, and on its 97.6% owned NX Gold Mine located in Mato Grosso State, Brazil. This update encompasses drill results received from the end of May through to the end of August 2019. Exploration drilling during the period was focused primarily on expanding recently announced discoveries as well as infill drilling ahead of the Company’s updated National Instrument 43-101, Standards of Disclosure for Mineral Projects (“NI 43-101”) compliant technical report and mine plan for the Vale do Curaçá Property, expected to be completed early in the fourth quarter of 2019.

HIGHLIGHTS

• High-grade massive sulphide mineralization continues to be encountered at the recently announced Siriema discovery, highlighted by hole FSI-42 that intersected 31.8 meters grading 2.22% copper including 5.0 meters grading 5.56% copper;
  
  
• Near-surface drilling adjacent to the Vermelhos Mine in the Vermelhos East Zone intersected 22.5 meters grading 4.60% copper including 8.0 meters grading 7.76% copper from 7.7 meters down-hole in hole FVS-418, one of the highest-grade intercepts drilled into the East Zone to date.
  
  
• A grouping of holes in the Deepening Extension of the Pilar Mine intercepted high-grade mineralization, including the deepest known mineralized intercept drilled to date in hole FC47139 that intersected 7.1 meters grading 6.50% copper including 4.1 meters grading 9.01% copper, approximately 80 meters below the previous known depth of mineralization at the Pilar Mine.
  
  
• Underground drilling to further evaluate the southern extent of the Pilar Mine orebody within the South Extension zone continues to intercept thick and high-grade mineralization, highlighted by hole FC34100 that intersected 25.5 meters grading 1.47% copper including 2.0 meters grading 5.85% copper.

Twenty-seven drill rigs are now operating throughout the Curaçá Valley, including fifteen within the Pilar District and twelve within the Vermelhos District. This includes two rigs operating at the recently announced Siriema discovery and four rigs operating on regional targets within the Pilar and Vermelhos Districts. There are currently three additional drill rigs operating at the NX Gold Mine.

SUMMARY

• Within the Vermelhos District, drill results during the period highlight the Company’s ongoing efforts to extend the known limits of mineralization throughout the Vermelhos System through further advancement of the recently announced Siriema discovery, drill testing new high-grade zones beneath the N8 Deposit (formerly known as Vermelhos West) and expanding the ongoing regional exploration efforts throughout the district.
  
  
  • Drilling at the Company’s recently announced Siriema discovery continues to show mineralized continuity within a higher-grade massive sulphide zone, with results highlighted by hole FSI-42 that intersected 31.8 meters grading 2.22% copper including 5.0 meters grading 5.56% copper. To date, Siriema has been interpreted as a mineralized zone extending approximately 400 meters in strike-length, approximately 20 to 50 meters in width, and from surface to a depth of approximately 250 meters. Mineralization at Siriema is hosted by multiple sub-vertical mineralized lenses that remain open to depth and to the east. Drilling continues to intercept a shallow-plunging east-dipping zone of high-grade massive-sulphide breccia mineralization trending to the north-northwest. Follow-up drilling as well as additional down-hole electromagnetic (“EM”) surveys along this massive-sulphide zone is ongoing.
    
    
  • Near-surface drilling of the Vermelhos East Zone during the period resulted in one of the highest-grade intercepts drilled to date into the zone in hole FVS-418 that intersected 22.5 meters grading 4.60% copper including 8.0 meters grading 7.76% copper from 7.7 meters down-hole. This intercept, along with deeper underground drilling highlighted by drill hole FVS-432 that intersected 27.6 meters grading 1.95% copper and 7.0 meters grading 4.48% copper including 3.0 meters grading 8.02% copper approximately 450 meters from surface, demonstrate the extent of the Vermelhos East Zone. To date, the zone has been interpreted as a series of lenses extending from surface oxides to a depth of approximately 550 meters and it remains open to depth and along strike.
    
    
  • Recent drilling at the N8 Deposit focused on further extending the known limits of the current mineral resource, targeting higher-grade mineralization below the previously envisioned open pit mine. To date, thicker and higher-grade mineralization has been encountered at the southern end of the deposit, which remains open to depth. The results in this area are highlighted by hole FV-146 that intersected 37.3 meters grading 0.73% copper including 3.0 meters grading 1.43% copper and hole FV-147 that intersected 8.0 meters grading 1.64% copper including 3.0 meters grading 2.92% copper.
    
    
  • Regionally within the Vermelhos District, exploration drilling continues to extend a north-northeast mineralized trend encompassing the Vermelhos Mine , East Zone, Siriema, the N8 Deposit and additional high-priority regional targets located to the north and south the Vermelhos Mine – a combined strike length of over 5.5 kilometers.
    
    
• Within the Pilar District, drilling during the period was focused on upgrade and exploration programs within and adjacent to the Pilar Mine, including the recently announced Baraúna discovery, located beneath the southern portion of the historic Pilar Mine. Four of these drill rigs are testing regional targets within the Pilar District, including evaluating mineralized extensions at the past producing Suçuarana Mine, located approximately 25 kilometers south of the Pilar Mine.
  
  
  • In the Pilar underground mine, re-prioritization of drilling in the Deepening Extension zone continues to significantly extend the known extent of high-grade copper mineralization within the zone. The results are highlighted by hole FC47142 that intersected 34.7 meters grading 2.29% copper including 18.6 meters grading 3.15% copper and hole FC47139 that intersected 7.1 meters grading 6.50% copper including 4.1 meters grading 9.01% copper. Hole FC47139 is the deepest hole drilled in the Pilar Mine to date, and the highlighted intercept is located approximately 80 meters below the previously announced deepest intercept in hole FC4885 (8.4 meters grading 4.02% copper and 6.9 meters grading 3.15% copper as outlined in the Company’s press release dated June 20, 2019).
    
    
  • Drilling within the Baraúna discovery continues to confirm the extent of mineralization within the zone. To date, mineralization has been delineated over a north-south strike length of approximately 450 meters, varying thickness of up to 30 meters and has been interpreted as extending from outcrop at the bottom of the open pit and connecting to mineralization at depth in the Pilar Mine. Current drilling is focused on mineralization above level -157, or approximately 110 meters below the bottom of the open pit. Drill results during the period are highlighted by hole FC2326 that intersected 50.0 meters grading 1.81% copper including 24.0 meters grading 2.32% copper and hole FC2426 that intersected 53.4 meters grading 1.43% copper.
    
    
  • Within the Pilar underground mine, drilling targeting extensions of known mineralization at the southern edge of the Pilar orebody from a new drill station located on level -300, continued to intercept new mineralization within the South Extension zone. This drilling has resulted in a significant expansion of known mineralization within the zone, highlighted by hole FC34100 that intersected 25.5 meters grading 1.47% copper including 2.0 meters grading 5.85% copper and 6.0 meters grading 1.85% copper.
    
    
• At the NX Gold Mine, where three exploration drill rigs are currently operating, drilling is focused on infill and extensional drilling of the previously announced Santo Antonio discovery (see press release dated April 18, 2019) as well as testing for continuity of the Brás vein in preparation of the Company’s updated NI 43-101 compliant technical report and mine plan expected to be released during the fourth quarter.

Expansions and extensions, as referenced herein, reflect mineralization not captured in the Company’s mineral resource and mineral reserve models used in the current (2018) NI 43-101 compliant mineral resource and reserves.

VERMELHOS DISTRICT

The Vermelhos District is located approximately 80 kilometers to the north of the Pilar Mine and Caraíba Mill complex and includes the operating high-grade Vermelhos Mine. Drilling is focused on upgrading, expansion and new discovery initiatives within and surrounding the Vermelhos Mine. In addition to near-mine programs, drilling is underway to evaluate regional targets identified during the Company’s regional airborne survey and subsequent data compilation work of the broader Vermelhos System – a north-south trend encompassing the Vermelhos Mine, East Zone, Siriema and the N8 Deposit that extends over 5.5 kilometers in strike length.

Twelve drill rigs are currently operating in the district including nine focused on resource upgrade and exploration programs within and adjacent to the Vermelhos Mine, while three rigs are focused on regional targets, including the recently announced Siriema discovery. Drill rigs in the district are comprised of three underground drill rigs and nine surface drill rigs.

Siriema

The recently announced Siriema discovery is the Company’s first regional discovery (see press release dated July 30, 2019 for the announcement of the Siriema discovery) and is located approximately 1.5 kilometers south of the Vermelhos Mine. To date, Siriema has been interpreted as a mineralized zone extending approximately 400 meters in strike-length, approximately 20 to 50 meters in width, and from surface to a depth of approximately 250 meters. The zone is interpreted to contain multiple sub-vertical mineralized lenses that remain open to depth and to the east. While the mineralization encountered to date is predominately disseminated, current drilling targeting down-hole EM anomalies continues to intercept a shallow-plunging east-dipping zone of high-grade massive-sulphide breccia mineralization trending to the north-northwest. Drilling along this trend was highlighted during the period by drill hole FSI-42 that intersected 31.8 meters grading 2.22% copper including 5.0 meters grading 5.56% copper. Follow-up drilling as well as additional down-hole EM surveys along this massive-sulphide zone remain ongoing.

The majority of the holes drilled during the period reflect twin-holes of previously announced RC drill results for NI43-101 validation purposes. Please see Figure 1 for a map of the Vermelhos System and Figure 2 for Siriema collar locations.

^{NSI indicates no significant intercept, based on a three meter mining width and cut-off grade of 0.18% copper for near-surface intervals and 0.68% for intervals below 200 meters down hole. Drill holes were drilled from surface. The length of intercept may not represent the true width of mineralization. Values may not add up due to rounding. From, to and mineralized intercepts are rounded to the nearest tenth of a meter.}

N8 Deposit

Drilling during the period at the N8 Deposit, previously referred to as “Vermelhos West”, was focused on extending the known limits of the current mineral resource and delineating higher-grade mineralization below the previously envisioned open pit mine. The southern end of the deposit remains open to depth, where to date, thicker and higher-grade mineralization has been encountered. New results in this area are highlighted by hole FV-146 that intersected 37.3 meters grading 0.73% copper including 3.0 meters grading 1.43% copper and hole FV-147 that intersected 8.0 meters grading 1.64% copper including 3.0 meters grading 2.92% copper. The holes continue to demonstrate that the deposit is open to the south and to depth. Hole FVS-146 was drilled approximately 120 meters south of the limit of the previously envisioned open pit mine (and approximately 85 meters below surface) while FVS-147 was drilled approximately 250 meters beneath the southern limit of the previously envisioned open pit mine.

Please see Figure 1 for a map of the Vermelhos System and Figure 3 for N8 Deposit collar locations.

^{NSI indicates no significant intercept, based on a three meter mining width and cut-off grade of 0.18% copper for near-surface intervals and 0.68% for intervals below 200 meters down hole. Drill holes were drilled from surface. The length of intercept may not represent the true width of mineralization. Values may not add up due to rounding. From, to and mineralized intercepts are rounded to the nearest tenth of a meter.}

Vermelhos East Zone Extension

The Vermelhos East Zone discovery (see press release dated September 25, 2018 for announcement of the Vermelhos East Zone discovery) is located approximately 100 meters to the east of mineralization comprising the main Vermelhos Mine orebodies and lies on the eastern side of an intrusive body. The zone of mineralization, to date, has been delineated from surface copper oxide mineralization to an interpreted depth of approximately 500 meters below surface.

During the period, drilling of the Vermelhos East Zone focused on confirming near-surface extensions of the modeled mineralization (below previously defined oxide mineralization) in advance of the Company’s upcoming NI 43-101 compliant mineral resource and reserve update and mine plan, as well as conducting underground drilling along the same structure at depth. Near-surface drilling confirmed the presence of high-grade copper mineralization highlighted by one of the highest-grade intercepts drilled into the zone to date in hole FVS-418 that intersected 22.5 meters grading 4.60% copper including 8.0 meters grading 7.76% copper from 7.7 meters down-hole. In addition, deeper underground drilling intercepted additional high-grade mineralization within the zone including 7.0 meters grading 4.48% copper including 3.0 meters grading 8.02% in hole FVS-432 from 357.2 meters down-hole. Additional drilling and follow-up down-hole EM surveys in this area are planned to further evaluate the potential relationship between high-grade intercepts within the zone.

Please see Figure 1 for a map of the Vermelhos System and Figure 3 for East Zone collar locations.

^{NSI indicates no significant intercept, based on a three meter mining width and cut-off grade of 0.68% copper. Drill holes were drilled from surface and level +248 in the Vermelhos Mine. Holes not included are either pending assay results, have been included in a different section of this press release for clarity of discussing drill results or were previously included in a prior press release. The length of intercept may not represent the true width of mineralization. Values may not add up due to rounding. From, to and mineralized intercepts are rounded to the nearest tenth of a meter.}

PILAR DISTRICT

The Pilar District encompasses the area surrounding the Pilar underground mine, Caraíba Mill complex and the past producing Pilar open pit and R22 Mines. Fifteen drill rigs, including eight focused on resource upgrade and exploration programs within the Pilar Mine, are currently operating within the district and three are operating on regional targets in the district. The drill rigs are comprised of seven underground drill rigs and eight surface drill rigs.

During the period, the Company re-prioritized drilling of the Deepening Extension where a grouping of deep holes, including the deepest hole drilled in the Pilar Mine to date, all returned high-grade copper intercepts and provide continued evidence that the Pilar Mine remains open to depth. New drilling in the South Extension encountered thick and high-grade mineralization in an area that had previously been modeled as narrow low-grade lenses at the southern edge of the Pilar orebody providing continued evidence that the Pilar Mine remains open to the south. In addition, drilling of the recently announced Baraúna zone continued to confirm mineralization within the zone, with several thick and high-grade intercepts drilled during the period.

Exploration drilling on the West Limb is expected to resume following completion of infill and Baraúna confirmation programs. Currently, four surface drill rigs are undertaking exploration drilling at Baraúna while four underground drill rigs are continuing to define the Deepening Extension and South Extension. The remaining four short-term core rigs are operating in the Deepening Extension and P1P2W mining areas.

The Deepening Extension

The Deepening Extension drilling is currently targeting mineralization on the East Limb of the Pilar Mine between level -725 and level -1300 approximately 1,200 meters to 1,750 meters below surface and approximately 100 meters laterally from the current level of the primary ramp (completed to level -915).

Underground drilling during the period re-prioritized testing the known extent of mineralization within the zone, including down-plunge exploration drilling beneath the deepest known extent of mineralization within the Pilar Mine. The results from the grouping of drill holes in this program were positive and are highlighted by drill hole FC47139 that intersected 7.1 meters grading 6.50% copper including 4.1 meters grading 9.01% copper, in what is now the deepest known mineralized intercept at the Pilar Mine, located approximately 80 meters below the previously announced deepest intercept of hole FC4885 (8.4 meters grading 4.02% copper and 6.9 meters grading 3.15% copper as outlined in the Company’s press release dated June 20, 2019). Additional results during the period continued to highlight the significance of the Deepening Extension zone. These results were highlighted by several drill holes including hole FC47142 that intersected 34.7 meters grading 2.29% copper including 18.6 meters grading 3.15% copper, hole FC48102 that intersected 19.5 meters grading 2.69% copper including 10.0 meters grading 4.10% copper. Exploration results from the Deepening Extension supports that the Pilar Mine is open at depth, where high-grade mineralization continues to be encountered over 350 meters below the deepest level of current development at the mine.

Please see Figure 4 for a north-south long section and Figure 5 for a level map showing collar locations of Deepening Extension drilling within the Pilar Mine.

^{NSI indicates no significant intercept based on a three meter mining width and cut-off grade of 0.68% copper. Drill holes were drilled from levels -670 and -740 in the Pilar Mine. Holes not included are either pending assay results, have been included in a different section of this press release for clarity of discussing drill results or were previously included in a prior press release. The length of intercept may not represent the true width of mineralization. Values may not add up due to rounding. From, to and mineralized intercepts are rounded to the nearest tenth of a meter.}

Baraúna Zone

During the period, drilling of the Baraúna zone continued to confirm the extent of mineralization previously identified in the historic database (see press release dated June 20, 2019 for the announcement of the Baraúna zone). To date, the zone has been delineated over a north-south strike length of approximately 450 meters, varying thickness of up to 30 meters and from outcrop at the bottom of the open pit connecting to mineralization at depth in the Pilar Mine – validation of the historic database remains ongoing. For planning purposes, drilling of the zone is focused on an area that, on average, extends 110 meters beneath the southern limit of the open pit mine. Drilling during the period was performed from surface targeting mineralization beneath the southern portion of the open pit mine. For reference, the pit floor is located approximately 230 meters below surface at its deepest part.

Please see Figure 6 for collar locations and Figure 7 for a north-south long section of the Baraúna zone.

^{NSI indicates no significant intercept, based on a three meter mining width and cut-off grade of 0.18% copper reflecting open pit potential. Drill holes were drilled from surface. Holes not included are either pending assay results, have been included in a different section of this press release for clarity of discussing drill results or were previously included in a prior press release. The length of intercept may not represent the true width of mineralization. Values may not add up due to rounding. From, to and mineralized intercepts are rounded to the nearest tenth of a meter.}

South Extension

Within the Pilar underground mine, drilling of the South Extension from a newly accessed drill station at level -300, continued to delineate a wide zone of mineralization previously modeled as narrow lenses at the southern edge of the orebody. Results during the period show a significant expansion of the South Extension zone in both thickness and grade. Drilling from the new drill station continues to target additional extensions of this zone to depth and to the south. These results are significant when combined with previously announced drilling from level -174, including hole FC3264 (21.0 meters grading 1.41% copper including 4.0 meters grading 3.54% copper and 31.9 meters grading 2.78% copper including 3.0 meters grading 5.63% copper as detailed in the Company’s press release dated June 20, 2019), as they provide further evidence that the Pilar Mine remains open to the south.

Please see Figure 8 for a north-south long section and Figure 9 for a level map showing collar locations of South Extension drilling within the Pilar Mine.

^{NSI indicates no significant intercept based on a three meter mining width and cut-off grade of 0.68% copper. The drill holes were drilled from level -300 in the Pilar Mine. Holes not included are either pending assay results, have been included in a different section of this press release for clarity of discussing drill results or were previously included in a prior press release. The length of intercept may not represent the true width of mineralization. Values may not add up due to rounding. From, to and mineralized intercepts are rounded to the nearest tenth of a meter.}

REGIONAL EXPLORATION

The Company continues to re-prioritize and test regional drill targets based on the ongoing data interpretation and targeting phase of the regional airborne geophysical survey. To date, over 50 high priority target areas have been identified and detailed analysis of each target area remains ongoing. Further drill testing of regional targets, located within the Pilar and Vermelhos Districts, remains underway, with two exploration drill rigs allocated to targets south of the Pilar Mine and four drill rigs located on targets both south and north of the Vermelhos Mine including follow-up drilling on the regional Siriema discovery within the Vermelhos District.

NX GOLD MINE

The NX Gold Mine is a high-grade producing gold mine, located in Mato Grosso State, Brazil. Historic and current production occurs within two adjacent mineralized quartz veins located along a northeast trend approximately 600 meters apart, known as Brás and Buracão, which are accessed via a single portal and decline. Beginning in late 2018, exploration drilling commenced to evaluate down-plunge extensions of the Brás and Buracão veins, as well as test for mineralization between the two veins, which resulted in the Santo Antonio Vein discovery located between Brás and Buracão. The Santo Antonio Vein, to date, has been defined over a lateral extent of approximately 400 meters, a down-dip distance of approximately 200 meters and remains open to depth (see press release dated April 18, 2019 for detail regarding the Santo Antonio Vein discovery).

Currently, three drill rigs are operating on the property, including one underground drill rig targeting further extension of the Santo Antonio Vein as well as continuity of the Brás vein. Please refer to Figure 10 for drill collar locations and Figure 11 for an east-west long-section of the NX Gold Mine. Drill hole ID nomenclature of SA and BSUG refers to Santo Antonio and Brás (underground drilling), respectively.

^{NSI indicates no significant intercept, based on cut-off grade of 1.40 grams per tonne gold. Drill holes were drilled from surface, except for BSUG holes which were drilled from level -205 in the Brás Mine. Holes not included are pending assay results. The length of intercept may not represent the true width of mineralization and reported intercepts reflect the entire thickness of the vein. Values may not add up due to rounding. From, to and mineralized intercepts are rounded to the nearest tenth of a meter.}

ABOUT ERO COPPER CORP

Ero Copper Corp., headquartered in Vancouver, B.C., is focused on copper production growth from the Vale do Curaçá Property, located in Bahia, Brazil. The Company’s primary asset is a 99.6% interest in the Brazilian copper mining company, Mineraҫão Caraíba S.A. (“MCSA”), 100% owner of the Vale do Curaçá Property with over 39 years of operating history in the region. The Company currently mines copper ore from the Pilar and Vermelhos underground mines. In addition to the Vale do Curaçá Property, MCSA owns 100% of the Boa Esperanҫa development project, an IOCG-type copper project located in Pará, Brazil and the Company, directly and indirectly, 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 Vale do Curaçá, Boa Esperanҫa and NX Gold properties, can be found on the Company’s website (www.erocopper.com) and on SEDAR (www.sedar.com).

NOTE ON NI 43-101 COMPLIANT TECHNICAL REPORT

The conversion of drill results presented in this press release into NI 43-101 compliant mineral resources and mineral reserves requires additional work and analysis that remains ongoing. Accordingly, the results herein may not be included in the Company’s upcoming NI 43-101 compliant technical reports, expected to be completed during the fourth quarter of 2019, due to the cut-off date of new drill data, the time required to complete such additional work and analysis, and other technical and/or economic reasons on completion of this work.

QUALITY ASSURANCE / QUALITY CONTROL

Vale do Curaçá Property

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 May 2019 to August 2019 third party drill rigs were operated by Major Drilling, 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 MCSA’s 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 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. 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 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 May 2019 to August 2019 third party drill rigs were operated by Major Drilling do Brasil Ltda. and Servitec Foraco Sondagem S.A. whom are independent of the Company. Drill core is logged, photographed and split in half using a diamond core saw at NX Gold’s 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 Goi nia (Brazil) for preparation and are analyzed by the certified laboratory of ALS Peru S.A., whom are independent of the Company. Gold content was determined by fire assay in 2018. Commencing in January of 2019, 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%.

Rubens Mendonça, MAusIMM, Chartered Professional – Mining, has reviewed and approved the scientific and technical information contained in this press release. Mr. Mendonça is a Qualified Person and is independent of the Company as defined by NI 43-101.

A PDF accompanying this announcement is available at: http://ml.globenewswire.com/Resource/Download/93c29895-58fe-4f77-bc6e-eac3ede8d93d