Pedra Branca

Stage 2 (Pedra Branca)

In February 2012 Avanco agreed terms with Xstrata Copper for a 100% interest in the Pedra Branca Project, in Carajas, Brazil and shareholders approved the all script offer on 5 April 2012.

The Pedra Branca Project and is located 50km of the Company’s 100% owned Stage 1, Antas Deposit.

The land package is mostly contiguous farmland with good access and no environmental limitations. The area benefits from excellent infrastructure within a district experiencing substantial investment from Vale’s development of “Serra Sul”, soon to become one of the world’s largest iron ore mines.

Situated on one of the main Carajas geological trends, mineralisation at the Pedra Branca Project is also IOCG (iron-oxide-copper-gold), with similar geological characteristics to neighbouring IOCG mines/deposits.

Discovered by Noranda in 2003 with the drilling of 9 diamond drill holes. Following Xstrata’s acquisition of Falconbridge (Noranda), twelve diamond drill holes were completed in 2007-2008 to test mineralisation at depth and along strike. Mineralisation was intersected in 17 of the 21 holes, over a strike length of at least 1.5 km.
The tenement portfolio includes a number of additional licenses considered prospective for new discoveries.

The current JORC Reported Resource at Pedra Branca is:

 

Table 1: Pedra Branca Mineral Resources. June 2013.
Grade Tonnage Reported above a Cut-off Grade of 0.4% Cu.

Domain
Category
Million Tonnes
Cu (%)
Au (ppm)
Cu Metal (t)
Au Metal (Oz)
East
Inferred
20.48
1.50
0.37
306,987
242,960
West
Inferred
26.34
0.96
0.30
252,588
256,583
Total
46.82
1.20
0.33
560,000
500,000

Pedra Branca orebodies from the south

An impression of the Pedra Branca underground

 

Local Geology

Pedra Branca is a typical IOCG deposit, and is located in the western portion of 850.318/00. It is comprised of two orebodies Pedra Branca East and West, divided by a brittle northwest fault.

Pedra Branca East

Geology is comprised of gneisses, granites and sheared meta-diorite, cut by late pegmatite dykes and mafic and felsic porphyritic. This is surrounding by deformed porphyry granite, embedded in mylonitic crystalline basement of the Carajás Mineral Province.

The shear zone runs EW-NE and is sub-vertical or dipping to the south. Underlying foliation is EW to NE with dip a of 70-80° south. The shear zone acts as a preferential conduit for fluids associated with subsequent hydrothermal mineralisation.

Mineralisation is characterised by the presence of chalcopyrite + pyrite ± pyrrhotite in tabular sub-vertical bodies, high tonnage and medium to high grade (20.48Mt @ 1.5% Cu, 0.37g/t Au and 0.82g/t Ag) striking over 800m in length and ranging in width from 10 to 50 meters and extending beyond known drilling to +800m depth.

Pedra Branca West

Geology is comprised of diorite, granite and gneiss in an anastomosing shear zone, EW to NE. In its northern portion, the area is cut by a late pegmatite, while porphyritic felsic dikes also occur. Again all embedded in the mylonitic fabric of the Carajás Mineral Province crystalline basement.

Structurally Pedra West is situated within a splay with the shear zone, with a sub-vertical foliation dipping to the south. Hydrothermal alteration together with sulphides, is predominantly an assembly of amphibole + magnetite ± biotite ± K-feldspar. Zoning occurs, increasing in intensity from west to east.

Mineralisation characterised by disseminated pyrite ± chalcopyrite, locally in veins and stringers along the foliation of the fault splay. Comprising of a system of veins, sometimes interconnected with disseminations, locally with some small gaps, it is high tonnage and low to moderate grade (26.34Mt @ 0.96% Cu, 0.30g/t Au and 0.69g/t Ag). The strike is +500m, with thicknesses ranging from 4 meters to 115 meters, and also remains open at depth at +600 meters.

 

GeologicalMapOfPedraBranca

Geological Map of Pedra Branca

 

PedraBrancaCrossSection

 

Drone Flyover of Site – October 2016

 

Drone Flyover of Site – September 2016

 

 

Drone Flyover of Site – June 2015