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San Lucas

To review the entire NI 43-101 San Lucas report please click here.

The San Lucas project consists of approximately 7,000 hectares along the Palestina fault, in the Guamoco area of the San Lucas gold belt. The San Lucas gold belt is host to the Frontino mine at its southern end, which has reportedly produced over 5 million ounces of gold. Quia is an early-mover into this significantly underexplored gold belt that has demonstrated potential to host world class gold deposits. A 5,000m Phase I drill program is now underway testing three priority targets with first results expected in the third quarter of 2011.

PROPERTY DESCRIPTION AND LOCATION

The San Lucas Property is located in the San Lucas Mountain Range, 38 km east of El Bagre and approximately 200 km northeast of Medellín in the Department of Bolívar, Colombia (Figure 4-1 and Figure 4-2). The Property consists of eighteen concession contracts in two semi-contiguous blocks separated by approximately 8.5 km (the northern and southern blocks). Concession corner points and boundaries are map located by Ingeominas using the Bogotá datum coordinate system. The total area of the concessions is 6,980 ha.


Figure 4-1: Location of the San Lucas Property, Colombia.




Historical Channel Samples and Grab Samples



Recent Results

Geochem Results Over Geology - Three Initial Target Areas Identified




Geochem Over Magnetics



Geochem Over Radiometrics - U



Geochem Over Radiometrics - Thorium



Geochem Over Radiometrics - K



IP Chargeability Targets - La Colina



IP Chargeability Targets Over Radiometrics - La Colina


ACCESSIBILITY, CLIMATE, LOCAL RESOURCES, INFRASTRUCTURE, AND PHYSIOGRAPHY

Access
The San Lucas Property is located in the San Lucas Mountain Range, 38 km east of El Bagre and approximately 200 km northeast of Medellín in the Department of Bolívar, Colombia, South America (Figure 4-2). The Property lies in the municipal districts of Zaragoza, EI Bagre, Segovia, Santa Rosa and San Pablo in Bolívar. Direct access is most easily attained via a 10 minute helicopter flight from El Bagre, 1.0 hour helicopter flight from Medellín, or 0.75 hour helicopter flight from Bucaramanga. The various mining villages, such as Marisosa, Mina Nueva and Chicago have clear fields or helipads that are suitable landing sites. Additionally, alluvial mining operators have driven tracks from El Bagre to the area west of Marisosa (e.g. proximal to concession 21505) with excavators. The tracks terminate 3 to 4 km west of Marisosa at Rio Tigüi. Road access between Medellín and El Bagre is attained via the 62 Highway, and the Remedios /Segovia / Zaragosa road (Figure 4-2). The 1536 m paved airstrip in El Bagre (IATA Code: EBG; elevation 84 m ASL) is serviced by regular commercial flights from Medellín. The flight from Medellín to El Bagre is approximately 1 hour by light aircraft. The airports in Medellín (MDE) and Bogotá (BOG) are major hubs serviced by a number of domestic and international air carriers.

Climate and Vegetation
Annual temperatures in the area of the Property average from about 30°C in the lower Rio Nechi, down to 18°C at higher elevations, with relative humidity ranging from 60 to 80% depending on the time of year. Rainfall is sufficient year round to keep the area green with dense vegetation; the rains are heavier in April to June and October to November. The remaining months of the year have less precipitation and define the dry season - January, February and December. The average annual rainfall in the area is 2.093.9 mm, the monthly average is 174.49 mm, the monthly maximum is 588.2 mm, the annual maximum is 4.093,7 mm, the monthly minimum is 0.0 mm, and the annual minimum is 765.9 mm. Weather statistics are covering a sampling period from 1961 to 1990 for Barrancabermeja (85 km to the southeast of San Lucas; 70 m ASL) and Bucaramanga (155 km to the east-southeast of San Lucas; 975 m ASL); The locations of Barrancabermeja and Bucaramanga relative to the Property are illustrated in Figure 4-2.

Physiography
Elevation at the Property ranges from approximately 500 m ASL in the river valleys to greater than 1500 m ASL at the highest mountain points. Topography is primarily controlled by lithology; river beds follow the grain of major north-south faults of the Palestina System and related southwest-northeast extensional fractures.

The Property area is blanketed with lowland evergreen broadleaf rainforest. Tall, broad leaved evergreens are the dominant tree type, forming a high, leafy canopy over the forest floor. The undergrowth is often restricted by the lack of sunlight at ground level, and generally consists of shade-tolerant shrubs, herbs, ferns, and small trees. El Bagre lies outside of the topography of San Lucas Mountains at approximately 55 m ASL.

Infrastructure and Local Resources
Modern infrastructure is not present in the immediate area of the Property. Mining villages in the San Lucas Mountains are linked by trails and the local population transports in most of their supplies by mule from larger towns such as El Bagre and Zaragosa (Figure 4-2). El Bagre, 38 km to the west of the Property, is the nearest town with reliable road access, electricity, and telephone/internet service. The principal economic activity in the area is the exploitation of gold, while agriculture, raising cattle and basic commercial activities are of lesser significance. Agriculture is carried out using traditional methods with low yields and soil deterioration over time. Cattle are raised primarily for meat production. El Bagre is major centre for alluvial gold mining in Colombia, and to some extent, basic mining and exploration amenities can be acquired here. Exploration projects carried out with the methods to be recommended herein would require extensive servicing from Medellín or Bogotá.

PROPERTY HISTORY

The area surrounding the San Lucas property has an extensive history of vein-type and alluvial gold mining dating back the Spanish colonial period (16th century). Gold mineralization associated with Segovia batholith, and their derived colluvial-alluvial occurrences, may be considered of the greatest importance in Colombian gold mining. Total production to date (both illegal and legal) in the Segovia-Remedios district is estimated to be 8 to 9 M oz Au.

A large number of artisanal scale operations have existed in the area of Segovia-Remedios and extending northward for tens of kilometers along the bifurcated margins of the Segovia batholith. In the early 20th century, several European mining companies were active in the district, exploiting mainly vein-type and to a lesser extent placer gold deposits. Companies once active in the district include the Choco Pacific Mining Company (Anglo American Gold Mines), the Frontino Gold Mines (in continuous production since 1852), and the Pato Gold Mining Company (owned by Placer Development Inc., an early incarnation of Placer Dome Inc.).

From a strictly hardrock perspective these deposits have yielded a variety of +1,000,000 oz. Au historical producers, including the El Silencio-Providencia Mine at Segovia, the La Bartola-Palmichela-La Castellana Mine at Remedios, and the El Limón camp near Zaragoza (Shaw, 2000). These mines typically have exploited considerable strike and dip extensions of their deposits: for example, the vein at the El Silencio mine has been worked over 2 km of its strike and 1800 m below surface (McQuiston & Shoemaker, 1981).

In the mid 1800s the English company "The Frontino and Bolivia Gold Mining Company Ltd." began production from several individual deposits in the Segovia-Remedios area. The two primary deposits that were the EI Silencio and La Bartola veins: 020° striking, 35° west dipping auriferous quartz veins hosted in granodiorite. Within the quartz-pyrite veins, native gold and silver was reported to occur with sphalerite, galena, calcite, scheelite, and pyrrhotite.

While Frontino Gold Mines is the largest underground producer in Colombia, it is a technologically antiquated operation. Production records and technical data are scarce and difficult to access. In 1973 and 1974, the annual milling rate was 145,000 t, average mill head grades were 7.80 g Au/t; 20.0 g Ag/t; and 0.37% Pb. Annual production was 1,150 kg (35,700 oz) Au, 4,500 kg (141,000 oz) Ag, and 300 t of Pb concentrate (McQuiston & Shoemaker, 1981).

Production from Frontino Gold Mines is estimated at 5.5 M oz Au since 1852.

Very few exploration companies had been exploring for gold in the area surrounding the San Lucas property in the last half of the 20th century due to the serious guerrilla problem that was prevalent in the district. Exploration did however continue along the Bagre and Otú Fault Mineralized Trends, about 20 and 40 km to the west, respectively, where several deposits were outlined. Exploration and mining activity was completed by Greenstone Resources Ltd. at the Oronorte district (which includes the El Limon and La Aurora deposits) and Dual Resources Ltd. on the El Carmen deposit (Figure 4-2). After 1995, these areas were held by Fisher-Watt Gold Company Inc. ("Fisher-Watt"). Reserves on the El Limon and La Aurora deposits were calculated by Fisher-Watt in 1996 as 40,610 t grading 14.0 g Au/t (Fisher-Watt, 2000; not NI43-101 compliant). The El Carmen deposit, which is located approximately 12 km northeast of El Limon, is also hosted in a north trending quartz vein that ranges in width from 0.10 to 3.0 m. Reserves on the Carmen Deposit were calculated by Greenstone Resources Ltd. in 1993 as 406,978 t grading 6.51 g Au/t (probable reserves; not NI43-101 compliant), and 365,910 t grading 10.27 g Au/t (possible reserves; not NI43-101 compliant). Fisher-Watt sold the concessions encompassing El Limon, La Aurora, and El Carmen in November, 2000; they are now reportedly held by Mineros S.A.

Alluvial mining is Colombia's main source of gold and platinum production (USGS, 2007). Several small to medium sized hand labour operations are active throughout the country; however, the most important alluvial gold deposits are located along the Nechi River in the Department of Antioquia where Colombia's largest alluvial gold mining operation, Mineros S.A. is currently working. In 1908, a French company began alluvial mining in this area by bringing in the first Yuba bucket ladder dredge from the Malaysia tin fields. The French company later was acquired by Consolidated Gold Fields of London under Pato Consolidated Gold Dredging, Ltd. and was subsequently purchased by Placer Development of Canada in 1932; followed by International Mining Corp. of New York in 1962. At this point the operations consisted of several Yuba dredges. In 1974, the dredging operations were acquired by a public Colombian company, Mineros de Antioquia, which established operations in El Bagre. During the 1970s and 1980s, Mineros de Antioquia was South America's largest gold producer operating six Yuba bucket ladder dredges. Mineros de Antioquia became Mineros S.A. in 2004. In 2005, Mineros S.A. was operating three dredging systems comprised of an overburden removing bucket wheel dredge in tandem with an alluvium mining bucket ladder dredge. The Company's operations are now downstream of El Bagre and their field operations are centered immediately outside of El Bagre.

GEOLOGICAL SETTING

Regional Geology

The western half of Colombia is transected by the Andes Mountains, which form a continuous (over 7000 km long) chain of highland along the western coast of South America. In Colombia, the Andes form three distinct north-south trending ranges (the Western, Central, and Eastern Cordillera). From west to east, the Western Cordillera (Occidental) and Central Cordillera are separated by the Cauca-Patia Depression; the Central and Eastern Cordillera (Oriental) are separated by the Magdelena Depression; the Guiana Precambrian Shield lies eastward of the Oriental Cordillera (Sillitoe et al., 1982; Figure 4-1). The Western Cordillera is Early to Late Cretaceous in age and consists of oceanic rocks (submarine volcanic rocks and related sills of tholeiitic basaltic composition, overlain by deep-water pelagic and turbiditic sediments). The Central Cordillera is Palaeozoic in age and consists of continental and oceanic rocks. The Central Cordillera contains widespread low-grade metamorphic rocks that represent shelf sedimentary sequences in the east and volcanic sequences in the west. The Eastern Cordillera is Palaeozoic in age and consists of continental rocks such as Jurassic red beds and Cretaceous carbonates and clastic deposits with little metamorphism. The San Lucas Property is located at the north limit of the Central Cordillera. Cediel et al. (2003) compiled geochemical and geophysical data from over three decades of preceding work and synthesized the tectonic assembly of the Northern Andean Block, which underlies eastern Ecuador, Colombia and Venezuela. They identified more than 30 distinct litho-tectonic and morphostructural units and their bounding suture and fault systems. The Northern Andean Block can be simplified into five tectonic realms that share internal genetic histories, from west to east they are the Western Tectonic Realm, Central Continental Subplate Realm, Maracaibo Subplate Realm, Guajira-Falcon Composite Terrane (northern Colombia), and Guiana Shield Realm (Figure 7-1). The Guiana Precambrian Shield is the basement beneath most of eastern Colombia and is characterized by high-grade metamorphic granulites. The Maracaibo Subplate Realm is the northwesternmost portion of the Guiana Shield. The Western Tectonic Realm contains lithiotectonic units with fragments of the Pacific oceanic plateaus, aseismic ridges, intraoceanic island arcs and/or ophiolite. The Western Tectonic Realm correlates with the physiographic Western Cordillera.


Figure 7-1: Tectonic Realms of Colombia (Cediel et al., 2003).


The Central Continental Subplate occupies a wedge between the Guiana Shield to the east, the oceanic Western Tectonic Realm to the west and Maracaibo Subplate Realm to the north (Cediel et al., 2003). The Central Continental Subplate is a compositionally heterogeneous lithotectonic realm with Precambrian and Palaeozoic constituents. The Central Continental Subplate is comprised of the Central Cordillera, the Magdelena Depression, and the Eastern Cordillera. The San Lucas Property is located within the Central Continental Subplate Realm.

Faulting in the Northern Andes is abundant and complex (Cediel et al., 2003). Large-scale strike-slip faulting is the key element in the tectonic evolution of the region. The Palestina Fault system is the controlling structural feature in the San Lucas area and includes the principal Palestina fault and a series of correlated structures to the south (Figure 7-1). The faults in the Palestina Fault System all have right lateral strike-slip movement, evidence of extensive shearing, and coalesce toward the south with the Romeral Fault System. The gold-bearing quartz-sulphide veins of the San Lucas Property are directly associated with the Palestina Fault System.

Gold mineralization in the Segovia-Remedios district is controlled by the Otú fault system, which is parallel to and approximately 40 km east of the Palestina fault system. At Frontino, mineralization is contained within second-order structures associated with a 330° flexure in the Otú Fault. The Otú (underlying El Limon, La Aurora, and Frontino), Bagre (underlying La Corona at its north end), and Palestina (underlying the San Lucas Property) fault systems are visible as north-south, anatomising lineaments on the topographic image in Figure 4-1. The three fault systems coalesce south of the Segovia-Remedios district. The Bagre and Palestina fault systems coalesce 20 km north-northwest of the San Lucas Property.

The north trending Palestina Fault System forms the boundary between the Cajamarca-Valdivia terrane and the San Lucas block (Cediel et al., 2003; Figure 7-1 and Figure 7-2). The Cajamarca-Valdivia terrane is composed of an association of pelitic and graphite-bearing schists, amphibolites, intrusive rocks and rocks of ophiolitic origin that attain greenschist through lower amphibolite metamorphic grade. Geochemical analyses indicate these rocks are of intraoceanic-arc and continental-margin affinity. The amphibolite-grade rocks of the Cajamarca-Valdivia terrane have been intruded by synkinematic granitoids. The granitoids are garnet-bearing, two-mica intrusives clearly displaying peraluminous (S-type) petrochemistry. The Triassic-Jurassic San Lucas block is dominated by composite metaluminous, calc-alkaline dioritic through granodioritic batholiths and associated volcanic rocks generated on a modified continental basement composed of the Chicamocha and Cajamarca-Valdivia terranes (Cediel et al., 2003).

A regional geology map illustrating the Cajamarca-Valdivia terrane and San Lucas block in more detail is presented in Figure 7-2. The San Lucas Property is positioned along the Palestina Fault system at the boundary of the Cajamarca-Valdivia terrane and San Lucas block. The stratigraphic column associated with this map is presented in Figure 7-3.

The majority of radiometric age-dates produced from the Colombian Cordilleras are of the K-Ar (biotite, hornblende, sericite)-type, and in this context are known to be highly susceptible to re-setting via subsequent thermal events, complicating in the process any associated time-contextual interpretations (Shaw, 2000).

Cáceres, et. al. (2005) report that emplacement of the Antioquia and Segovia batholiths began in the upper Palaeozoic (405.5 to 245 Ma). Feininger, et. al. (1972) reported a K-Ar age of 165 Ma (Figure 7-4). More recent work suggests this age is not appropriate, and the Segovia batholith may be post-Cretaceous in age.

Based on fission track age dating of vein and wall rock samples in the Segovia-Remedios area, Echeverry (2006) reported the estimated ages of cooling below 200°C (zircon) for the Segovia batholith is late Cretaceous (68.4 ± 5.5 to 84.1 ± 5.5 Ma), and below 100°C (apatite) is Paleocene (59.1 ± 4 to 64.7 ± 6.3 Ma). The estimated latest age for hydrothermal activity was reported as Eocene (47.7 ± 2.9 Ma), based on data from fission track age-dating of apatites in the wall rocks adjacent to veining (Figure 7-4).


Figure 7-2: Geology of the San Lucas area (Tapias et al., 2007).



Figure 7-3: Stratigraphic column of the San Lucas area (source: Tapias et al., 2007).



Figure 7-4: Radiometric age dates from the Segovia batholith.


Property Geology

The central area of the San Lucas Property is underlain by Precambrian orthogneiss units elongated in the NS direction (Orthogneissic rocks; Figure 7-5) along the Palestina Fault system. These well foliated, quartzo-feldspathic, banded gneisses have mm scale biotite and hornblende rich segregated layers (Turizo, 2005). A lesser proportion of the entire unit is comprised of amphibolitic, hornblende gneissic and granodioritic gneissic rocks. The entire unit is inferred to be of Precambrian age. The metamorphic grade is generally lower amphibolites facies (with quartz, plagioclase, biotite, muscovite, potassium feldspar and rarely andalusite alteration assemblages). The northern block and extreme west of the southern block are underlain by black graphitic shales and amphibolites of the Cajamarca-Valdivia terrane. This terrane also consists of alternating units of quartzite and quartz schist (with sericite, muscovite, and chlorite alteration).

This unit forms a vast NS swath approximately 20 km in width (Amphibolitic rocks; Figure 7-5). Good outcrop exposure has been found in the Puna, Pocuné, Caribona and Platanal river beds (Turizo, 2005). The units have been established as Lower Palaeozoic in age based on the presence of brachiopod fossils and low degree of metamorphism (Tapias, et. al., 2007). The majority of the southern block and area to the east of the Property is underlain by the San Lucas block, which is primarily comprised of Jurassic granodioritic rocks of batholithic origin (Granodioritic rocks; Figure 7-5). The composition varies from granodiorite, hornblendite, to quartz-monzonite, with the former being the dominant facies. Locally, quartz gabbros (Rio Bagre) and monzonites (Segovia) are present. The western edge of the San Lucas block is terminated by the Palestina fault system, which transects the Property. A map of the Property scale geology and selected artisanal gold mine locations is presented in Figure 7-5. In the area of Sur de Bolívar, the Segovia batholith is locally known as the Norosí batholith.


Figure 7-5: Geology and artisanal mine sites of the San Lucas Property.