Home

Borba 2 Copper Project

THE BORBA 2

CMT_Borba-2_47

A complex and diversified geology, endows Portugal with considerable mineral potential. Mineral exploitation from world-class deposits include, Neves-Corvo (Cu, tin) operated by the Lundin Mining and Panasqueira (W) tin operation by Almonty, Portugal is presently one of the main EU producers of copper, tin and tungsten concentrates and an important world producer of ornamental stones.

Portuguese territory covers half of the Iberian Pyrite Belt (IPB) which is considered the main metallogenic province of the European Union, where occurrences of polymetallic massive sulphide occur.

The Borba 2 concession permit, which consists of four projects, is located 160 km east of Lisbon and approximately 70 Km east of Évora the local provincial capital. The recognized potential of this sector to host precious-metal and base metal mineralization is enhanced by the presence of past producing mines and abundant Cu and Au mineral occurrences in shear zones and epithermal systems associated with intra-Ordovician volcanism.

The Borba 2 permit covers an area of 328 sq. km and represents an elongated polygon with the longest side at 40 km long and the widest part at 11km.

Previous Exploration Includes;

The Rio Tinto Group which explored the area for epithermal gold
deposits during the early 1980’s. They were followed by Carnon Holdings Ltd, in the early 1990’s, by Auvista Minerals during the period 1996-1998, by Rio Narcea Gold Mines in a JV with Kernow Resources (2005-2007) and more recently by Colt Resources.

Our most Advanced Asset the Miguel Vacas Past Producing Copper Mine

  • is Located 5 km due South of the town of Vila Viçosa. with good access and infrastructure

History:

Exploration started in 1925-1978 and onwards with various companies, who conducted sampling, drilling and some geophysics.

  • 1979: Minargol – Sociedade Mineira de Argozelo SARL acquired Miguel Vacas concession from EMIL
  • 1981-1990: Minargol exploited part of the oxide copper mineralization at Miguel Vacas by open pit method, with heap-leaching electrolytic recovery of copper. The company processed 464,100 ton of Ore @ an average grade of 2.1% Cu. Production was then halted.


The halting of mining operations by Sociedade Mineira de Argozelo was due to the financial difficulties of its holding company Minargol, which went bankrupt, mostly as a result of their tin operation in Argozelo in (Northern Portugal).

  • 2005-2007: Rio Narcea Gold Mines SA carried out exploration & reassessment of old data
    In 2006 Rio Narcea Gold Mines trenched the north pit wall, which returned 13.5 meters avg 1.6% Cu, including 2 meters assaying 4.9% Cu.

Mineralization:

Copper mineralization occurs in brecciated zones and the impregnation of black/grey shales in the oxide zone, including Malachite, Libethenite, Crisocola, Atacamite and Covelite.

  • Hosted by Silurian sericitic, graphitic and siliceous schists, near the contact with Cambrian/Ordovician carbonates.
  • Consisting of a brittle shear zone, mineralization originates in breccias of two types, with disseminated copper minerals:
    (1) quartz breccia; (2) schist breccias (the former richer than the latter)
  • the vein strikes NNW and dips at 70° and is up to 20-metre-wide structure in some areas, sub-concordant with host units
  • Main structure recognised in outcrop for ca. 2 km strike length, which has been confirmed by drilling down to >250 m.
  • Transition zone between oxide and sulphide copper mineralization occurs at interval 72-90 meters deep
  • Sulphide mineralization zone >90 m deep, consisting mainly of chalcopyrite, pyrite and minor arsenopyrite
  • Copper grades normaly in the 1% – 2% range; not decreasing significantly from the oxide to the sulphide zone
  • Some parallel copper mineralized structures, identified but poorly investigated, this may add to the mineralization on the project.
  • Very limited mining to date:


The deposit remains open along strike and down dip.

MIGUEL VACAS

Highlights:

CMT_Borba-2_Miguel-Vacas_48
  • Shallow secondary copper minerals in brecciated zones and impregnations in black/grey shales in the oxide zone, including Malachite, Libethenite, Crisocola, Atacamite and Covelite.
  • Primary cupriferous, almost exclusively associated with brecciated zones with Chalcopyrite + quartz + carbonate from 80 metres depth.
  • Mined via open pit in the 1980’s—approx. 900 tons of copper metal in concentrate produced at an average grade of 2.1% Cu.
  • The halting of mining operations at Miguel Vacas in 1990 was due to the financial difficulties of its holding company Minargol, which went bankrupt as a result of their tin mining operation in Argozelo (Northern Portugal).
  • The deposit remains open along strike and down dip. Mineralization is traced over 1.7 km.


BUGALHO MINE

History:

Developed in 1866 the mine has seen intermittent mining until the early 1900’s. Records indicate mining down to a depth of 200m on nine levels.

Geology consists of
Silurian dark-grey shales with intercalations of black cherts, quartzites and graphitic
phyllites (Charneca Fm), adjacent to a major NE-SW deep seated fault zone (Messejana
fault ).

Metalogenesis:

Quartz-cemented breccias emplaced on east branch (splay?) of the Messejana Fault zone.
Mineralization is thought to be related to a late Hercinian mineralizing event.

Structure:

The Mineralization is associated with a 1km long section of the fault zone. Includes three
main veins that have been mined in the past: Vein 1 (main vein), up to 1.2 m thick, mined over 800m along strike; Vein2 – , average 1.3m
thickness; Vein 3 – no records on file.

Mineralization:

  • Primary Copper mineralization: chalcopyrite and pyrite within quartz-carbonate
    breccia matrix. Accessory arsenopyrite with occasional elevated gold assays;
  • Supergene Copper mineralization: malaquite, hematite and scorodite.

Past Exploration Results And Upside Potential:

Dump samples of silicified and sheared acid tuffs from the Bugalho mine area assay up to 9.14
g/t Au and 0.35% Cu. The mineralization is from a wide NE-SW trending shear zone that can be
mapped on at least 5 km along strike.

MOSTARDEIRA MINE

Mostardeira Copper mine is located approximately 2 km south of the town of Estremoz and 4km north of the NW limit of the tenement. The mine operation was focused on a wide (up to 10 m thick) anastomosing WSW-ESE trending vein system that is developed on at least 700 m along strike and is open to both directions. The vein system is hosted by Silurian and Devonian
metasediments.

This shear zone has been historically mined for Cu with most of the mining works concentrated
along a thin high-grade Cu zone (<2m) that was probably running over 5% Cu. The records on
gold production are not available.

Sampling by Rio Narcea bought by Lundin

Previous Exploration:

Channel sampling by Rio Narcea Gold Mines in 2016
highlights:

  • 18.6m grading 0.8 g/t Au, 0.3% Cu and 20 g/t Ag
    Including
  • 4.9 m grading 2.1 g/t Au, 0.76 % Cu and 64 g/t Ag

ALMAGREIRA TARGET

Mineralization:

Epithermal mineralization occurs in altered volcanics and carbonates and is mainly controlled by an E-W structure, that extends at least 400 metres along strike and is open at depth. The mineralized zone occupies the core of a second order anticline with acid volcanics flanked by Silurian shales, phyllites and graphitic phyllites.


Previous Exploration:

  • Hole PAM-1 includes an interval of 5.45 m grading 1.53 g/t Au, including 2.47m grading 2.44 g/t Au. The highest individual value obtained came from a gossanous quartz-dolomite altered marble grading 5.77 g/t over an intercept of 0.75m. Banded carbonatization and low-temperature silica alteration occur thoroughly in the hole. Zones of poor recovery are interpreted to represent karst fill features.
  • Hole PAM-2, located in the same zone includes an intercept of 17m grading 0.5 g/t Au, including an interval of 2 m grading 3.7 g/t Au. The mineralized zone coincides with sections of intense silica-carbonate alteration with several massive gossan zones and localized fresh sulphide dissemination (chalcopyrite and pyrite).

Join Our Mailing List

Unsubscribe at any time
Thank you! Your submission has been received!
Oops! Something went wrong.