The Touro deposit is hosted in a continuous, highly deformed and metamorphosed horizon of metabasite and paragneiss of the Arinteiro Unit (Ordenes Complex). This horizon outcrops along the flanks and hinge zone of a broad north plunging antiformal structure for at least 8km along strike and up to 2km across strike. It extends beyond the project area and is open to depth.

The Arinteiro Unit is composed mainly by metabasites with minor lenses of ultramafic rocks and paragneisses (Gomez Barreiro, 2007). The mineralogy, grain size, and homogeneity of the metabasites are variable, most of the rock types are hornblende-plagioclase rocks with or without garnet (almandine), clinopyroxene (salite), and quartz. The rocks have undergone varying degrees of cataclasis commonly associated with retrogressive greenschist facies assemblages. The metabasites are strongly deformed showing tectonic banding, intrafoliar folds and oriented nematoblastic texture. Very locally, relict igneous textures have been described supporting the theory of a gabbroic protolith (Castineiras et al., 2002; Gomez Barreiro, 2007).

The metasediments of the O Pino Unit lie above and below the metabasites that have been interpreted as representing a flysh sequence (Gomez Barreiro, 2007). This unit is composed mainly of paragneisses with predominant greywacke composition. Minor pelitic metasediments, biotitic shists (sometimes rich in graphite), and amphibolite gneisses are also described in this ........

Open pit copper mining operations have been conducted within the Touro project site during the 1970s and 1980s before being shut down in 1986 due to low metal prices. Old pit walls are presently standing well and vehicular access exists into the pit areas. Some pit dewatering will be required prior to new development work, particularly in the Vieiro pit.

Redevelopment of copper mining operations will use conventional, open pit methods, mining from benches on 10-m vertical intervals. Contractors' small-to medium-scale mining equipment will be used, including: rock drills capable of drilling 102- to 127-mm-diameter blastholes, hydraulic excavators and/or front-end loaders with bucket capacities of approximately 6-13 m3, off-highway trucks with 55- to 91-t payload capacities, and suitably sized support equipment.

Mining Pits/Phases.
Seven pits were developed using Lerchs-Grossmann (LG) pit shells based on a copper price of $2.60/lb, the final pushbacks for which are: Arinteiro-Vieiro, Arca 2, Bama 2, Brandelos 2, Monte 3, Monte 4, and Monte 5. Arinteiro-Vieiro has high Cu grades along with a high stripping ratio, and is the primary development target in the early years of operation. Five initial phases were designed to improve mill head grades during the first 6-7 years of operation, targeting smaller pit extents identified by $1.75 and $2.00/lb Cu LG shells. These phases are identified as: Arca 1, Bama 1, Brandelos 1, Monte 1, and Monte 2. "Monte" ref ........

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