Limão

Summary

The Limão property is situated in the Tapajós Gold District in Central Brazil and consists of two exploration licences totaling 10,406 hectares. The Tapajós region was one of the primary alluvial gold sites in Brazil. The area became a significant producer in the 1980s by a flood of small scale alluvial miners called garimpeiros. Peak gold production in the region occured in the late-1980s with as many as 500,000 garimpeiros. Real production numbers are unknown but estimates range from 500 to 800 tonnes of gold.

Between 1987 and 1990, Mineração Pompeia carried out systematic prospecting work in the area which included geochemical and geophysical surveys followed by a small drill program in an area previously mined by locals. Holes drilled under an open pit returned promising results such as 47 g/t Au over 13 metres and 18.7 g/t Au over 6.8 metres.

During 1994 and 1995, Barrick Gold conducted a review of the area and began to revaluate the data and completed preliminary geological and geochemical reconnaissance of the area. As expected a gold anomaly was defined in the open pit area. Additionally, several gold anomalies were defined outside the area of the open pit.

Location and Access

The Limão Project is located in the central-northeast portion of the Tapajós Gold District. More specifically the property is located approximately 180 kilometres south of the city of Itaituba (pop. 70,000) and 30 kilometres east-north-east of the oldest and most important prospecting community in the region - Cuiu-Cuiu. Access to the property is exclusively by air from Itaituba.

Regional and Property Geology

The area of the Limão Project is located in the Amazon Craton, in the Central Amazon sub-province. It is composed of the Cuiu-Cuiu Metamorphic Suite, representing the undivided basement formed by migmatized gneisses, granitoids of varied compositions, relics of amphibolites, rock of granulite facies, and remains of a volcanic sedimentary Jacareacanga Group.

During the mid-Proterozoic (Ma) the area was influenced by a widespread magmatic-volcanic event and sedimentation represented by the Uatumã Group. This is further divided into two major units; the basal unit called the Iriri Formation, composed of acidic volcanics rocks, associated tuffs and sediments and intrusive Maloquinha Suite represented by acidic intrusive rocks. The Maloquinha Granite is hosted preferentially in epizonal crustal portions, exhibiting alkaline metaluminous characteristics and probably is responsible for the formation of prospective sites for gold mineralization.

In the Cenozoic (Ma), deep tropical weathering resulted in the oxidization of the rocks and formed the present day drainage and landscape.

Mapping and geophysics by Barrick determined two main geological domains on the property. Domain 1 occupies the north and south portions of the mapped areas and Domain 2 occupies the central portion. Mapping of the two domains is further supported by the magnetic signature.

Domain 1 is typically characterized with granites of the Maloquinha type and is suggested to be sub-volcanic in origin. Rock belonging to the Domain 2 show gneissic textures and are granitic to monzonitic in composition. The granitic rocks in Domain1 are considered to be younger than the rocks in Domain 2. Ground magnetic surveys show that the gneisses in Domain 2 are associated with a zone of low magnetic gradient.

Exploration Results

The Limão Property is situated along the NW-SE Tocantinzinho Trend. This trend hosts notable gold properties such as; Eldorado's Tocantinzinho Property and Magellan Mineral’s Cuiu-Cuiu property. Exploration and sampling by Amerix during 2009 and 2010 confirms that the gold mineralization on the property is associated with syenitic or alkalic rocks containing disseminated pyrite and fracture infills of massive pyrite. Gold deposits clearly linked to alkaline magmatic rocks host many world class deposits such as the as the Cripple Creek Au Deposit in Colorado, Porgera Au Deposit in Papua New Guinea, and several of the gold deposits in the Abitibi Greenstone Belt such as the Malaritic Deposit.

Drilling in the pit area during the late 1980’s returned impressive gold values. Two holes drilled under an old pit returned 47 g/t over 13 metres and 18.7 g/t Au over 6.8 metres. Historic results from the drilling show consistent gold values over the interval as well as high copper values.

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Results from geochemical surveys during 1994 and 1995 by Barrick continued to show impressive results. Barrick’s work noted that the gold mineralization in the area is directly associated with a syeno-granitic body rich in pink K-feldspar belonging to the plutonic-volcanic event Utamã. Fifteen samples taken by the Barrick geologists from the pyrite rich syeno-granitic rocks returned values ranging from 1.75 g/t Au to 25 g/t Au.

Amerix Work

The Company’s review and due diligence of the area consisted initially of satellite/aerial photography and location of the artisanal workings. In 2009 a crew was mobilized to the property and re-established the camp and airstrip. Initially a small grid was established for sampling and mapping control over the pit area and other artisanal workings. A total of 11 float samples were taken from sulphide-rich syeno-granitic rocks located in the pit area. Results range from 2.37 g/t Au to 106.6 g/t Au with an average of 38.5 g/t Au or 1.12 oz/t Au. Sample results from the syeno-granitic rocks are summarized in the following table.


Additional sampling was conducted during 2010 and confirmed gold mineralization in the pit area. Sample # TSBDH5 of the mineralized syenite returned 3.09 oz /t Au or 106.1 g/t Au.

The Company believes these samples to be representative of bedrock mineralization at the bottom of the open pit which was previously mined by local miners. The open pit is now filled with water and is believed to be 20 metres deep. In 2010, the old core was located and one sample # TSBDH3 from the mineralized zone returned 1.01 oz/t Au or 34.77 g/t Au.

A total of 1841 one-metre auger samples were taken at 20 metre intervals along parallel north-south lines spaced at 100 metre intervals. Sample results from the 2009 and 2010 geochemical surveys located several gold in-soil anomalies and reconfirmed previous operator’s results. Three grids (North, Central and South) were established for sampling and mapping control. Sampling defined a strong east-to-west anomaly on the central grid measuring 1,300 metres long. The pit area is located 200 metres north of gold-in-soil anomaly. The northern grid covers 1.62 square kilometres and several gold-in-soil anomalies were defined. The most notable anomaly covers an area of 300 by 200 metres located approximately 400 metres north-northwest of the open pit area. The Southern grid covers an area of 0.45 square kilometres and a well defined, 200-by-200 metre gold-in-soil anomaly was defined apploximately located over 1500 metres south of the historic drilling. Visible gold was observed in the quartz veins in this area and rock sample results returned high grade gold values.

Figure 1 as Property & Grid Work - Location Map

Figure 2 as South Grid

Photo Gallery

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Project Info

To view the NI 43-101 click on the link below.
May 2011		NI 43-101 Technical Report Limão Gold Project, Brazil		PDF	(28.24 MB)