BMR’s 100%-owned Punitaqui copper mine has been on care and maintenance since April 2020 when the previous operators were forced into bankruptcy by its creditors due to the rapid fall in copper prices from mid-2018 to its bottom of $2.03/lb in March 2020. 

The operation leverages all necessary fixed assets and infrastructure, excellent road access, ready availability of water, existing power lines, majority of operational permits in place, and widespread mineralization. Punitaqui boasts a nine-plus year operating history and is on track for resumption of underground mining in late 2022 followed by copper concentrate production soon after. 

After acquiring the assets in March 2021, BMR was quick to begin redevelopment of the operation. The Company has since recommenced activities for the resumption of mining and milling. Sale of copper concentrate will be carried out in conjunction with an aggressive two-phase regional exploration campaign to better define historical mineral resources and add new resources for mining in the future.

Cinabrio is the original underground mine which was the source of feed to the copper concentrating plant for over eight years and has remaining ore to be processed. The San Andres zone has existing underground access and copper mineralization up to 30 meters wide. The Dalmacia zone also has underground access and exhibits copper mineralization widths up to 50 meters. Regional targets including the Cinabrio Norte zone offer near-term “blue sky” exploration and district-scale potential for BMR. 

The re-start of mine operations is projected to begin late 2022 with full commissioning expected shortly after. Punitaqui has the potential to generate an annual EBITDA of up to US$50 million at or above a copper price of $4.00/lb.

Punitaqui - Cinabrio Norte

Key Facts

Location:
12 kilometers south of the city of Ovalle and 25km north of the Punitaqui Processing Plant.
Ownership:
100% BMR
Status:
Exploration Resource Drill Target
Metals:
Cu, Au, Ag
Current Exploration Activities:
Phase 1 2021-2022 BMR Drilling Completed
Mineral Resources:
-833,000 tonnes indicated at 1.01% Cu & 4.57 g/t Ag at a 0.7% Cu cut off. -1,078,000 tonnes inferred at 0.98% Cu & 4.91 g/t Ag at a 0.7% Cu cut off.
Mining & Processing Concept:
Plant with designed for 3,600tpd and has the capacity for 4,000tpd. Standard Process: crush, grind, floatation process that produces Copper – Gold concentrate.

Overview

The Cinabrio Norte target represents a potential northern extension of the main Cinabrio mine orebody, which historically was the primary source of ore feed to the Punitaqui copper processing plant for eight-plus years. Cinabrio Norte is an underground target located 110m north of the existing Cinabrio underground workings on level 220m.  

The host to mineralization at Cinabrio Norte is a package of sedimentary rocks that occurs above a sequence of andesitic volcanics, and sediments derived from those volcanics during the early stages of a marine transgression. The sedimentary package includes calcareous sandstones and conglomerates with intercalated calcareous black shales and carbon bearing fine grained sandstones. 

This package averages around 15 metres thickness. Copper mineralisation including chalcopyrite and bornite was emplaced by feeder structures into the host sedimentary horizon just after sequence was deposited.

At Cinabrio Norte, the Phase 1 drill program consisted of 53 holes with a total of 13,731 meters drilled as a series of step-out holes to test the target stratigraphic unit along a 400m strike (north-south) to a depth below surface (“down-dip”) of 350m. The current drilling has outlined a significant zone of high-grade mineralization in the northern portion of the target zone which remains open at depth. 


Once permitting and detailed mine design are completed, the Cinabrio Norte zone could be accessed for mining of copper ore by completing minimal amounts of underground development owing to Cinabrio Norte’s proximity to Cinabrio -  only ~110m north of the 220m level in the Cinabrio mine. The Cinabrio Norte zone remains open at depth, which BMR plans to investigate via underground drilling once access has been established. 

Exploration History

From 2007 – 2010, Tamaya Resources Limited, undertook a feasibility study and constructed a plant and commenced mining for a short time. Tamaya Resources targeted Cinabrio Norte with a very limited shallow drilling effort in 2008.  In 2010, Glencore International Plc acquired the project, finished allocating needed capital, including upgrading plant and the underground development, then resumed operations at Cinabrio.  Glencore then sold the project, in late 2018, to Xiana Mining. In 2018, Xiana Mining Inc. increased exploration efforts and initial development of the San Andres target. In 2020, Xiana completed a limited follow-up drill program at Cinabrio Norte. Historic hole CNS-20-01 drilled was drilled completely within the target stratigraphic unit resulting in multiple mineralized intercepts and, most importantly, confirmed the presence of the target unit for over 200m of strike length with anomalous copper sulphide mineralization.  The target stratigraphic unit has been mapped along a north-south strike from the Cinabrio mine for 400m.

Geology & Mineralization

Cinabrio Norte is an Iron Oxide Copper Gold (IOCG) type manto deposit. 

Mineralization at Cinabrio Norte has a continuous strike length of about 400m, is up to 30m thick and has been drill traced to a depth of around 350m. The mineralization is predominantly chalcopyrite with minor bornite and pyrite, dips steeply to the east and is occasionally locally faulted with small offsets. 

The regional geology of Jurassic to lower Cretaceous age consists of a sequence of volcanic rocks (lavas, conglomerates and andesitic breccias) with marine sediment collations (shales, fossiliferous limestones and thin layers of sandstones). This sequence is affected by a granitic intrusive (diorites, granodiorites) of Upper Cretaceous age.

The manto mineralization is hosted by a regionally extensive marine sedimentary rock unit within an andesitic volcanic sequence. The sedimentary rock unit is comprised of dark coloured shales, volcanoclastic sandstones, volcanoclastic sedimentary breccias and conglomerates and fossiliferous limestones.

The structural framework of the district is represented by stress and compression forces, which is reflected in north-south, northwest, and east-west tectonic orientations. The structural fabric of the regional and district character controls the location of copper mineralization. The mineralized sedimentary unit is deformed and rotated by extensional faulting resulting in multiple structural repetitions of the mineralized sedimentary unit exposed at surface. The stratigraphy has been consistently rotated to the east resulting in a north-south striking and east dipping sequence. 

Mineralization is variable and believed to be controlled by mineralizing fluids focused along structures within the footwall rocks. Syngenetic pyrite is a common constituent of the sedimentary unit.

Hanging wall alteration is sometimes absent but can reach up to 30 metres thick above the mineralized sequence. There are three types of hanging wall alteration which is sometimes pervasive in the sedimentary sequence.

    • Silicification and sericite alteration 
    • Silicification with potassic alteration including epidote and specularite 
    • Silicification and sericite alteration with strong tourmaline alteration 

In the feeder/stringer zones in the basal andesitic sequence, copper mineralization is comprised mostly of bornite associated with potassic alteration, silicification and occasional epidote. These feeder structures appear to be part of a structural network that also caused the initial depressions that were filled with the chemically favourable host sequence. They were later reactivated during compression that forced metal bearing fluids into the sequence along these structures.

Current BMR Exploration

At Cinabrio Norte, the Phase 1 drill program consisted of 53 holes with a total of 13,731 meters drilled as a series of step-out holes to test the target stratigraphic unit along a 400m strike (north-south) to a depth below surface (“down-dip”) of 350m. The current drilling has outlined a significant zone of high-grade mineralization in the northern portion of the target zone which remains open at depth. Once permitting and detailed mine design are completed, the Cinabrio Norte zone could be accessed for mining of copper ore by completing minimal amounts of underground development owing to Cinabrio Norte’s proximity to Cinabrio -  only ~110m north of the 220m level in the Cinabrio mine. The Cinabrio Norte zone remains open at depth, which BMR plans to investigate via underground drilling once access has been established. 

Technical Reports

November 20, 2018: NI 43-101 Technical Report for the Punitaqui Project Chile By JDS Energy & Mining Inc. for Xiana Mining Inc.

A NI 43-101 Technical report will be released within 45 calendar days of the resource estimate press release dated August 16, 2022.