Mariana Commences Fourth Drilling Programme at Las Calandrias Gold-Silver Project, Argentina
VANCOUVER, BRITISH COLUMBIA -- (Marketwire) -- 08/23/11 -- Mariana Resources Ltd. (TSX: MRY)(AIM: MARL) ('Mariana' or 'the Company'), the AIM and TSX quoted exploration and development company focused in Argentina and Chile, announces that the fourth drilling programme at its 100% owned Las Calandrias Gold-Silver Project ('Las Calandrias'), in the prospective Santa Cruz gold district in southern Argentina (Figure 1) has commenced.
Overview
-- Fourth drilling programme will comprise at least 10,000m with minimum of
5,000m in the first stage of a two stage programme.
-- Testing seven new targets (Figure 2) at Las Calandrias, all outside the
outlines of the Calandria Sur and La Calandria initial resources
announced on 11 July 2011.
-- Loma Verde and La Picasa targets cover a 200 to 300m x 500m area of
prospective volcaniclastics adjacent to the Calandria Sur rhyolite dome.
The areas coincide with a very strong gold lag anomaly 30-750 ppm Au.
-- Volcaniclastic-hosted mineralisation consists of multiple sub-metre
zones of quartz veins/veinlets, breccias and stockworks related to
broad zones of silicification.
-- Rock chip sampling in volcaniclastic-hosted mineralisation averaged
0.55 g/t Au (151 samples) with up to 0.5m @ 11 g/t Au.
-- Best trench assays are 20m @ 1.0g/t Au (Loma Verde) and 20.8m @
1.5g/t Au including 8.4m averaging 2.9g/t Au (La Picasa).
-- A previous drill hole in this area intersected encouraging
volcaniclastic-hosted gold mineralisation - CSD261 35.5m @ 1.8 g/t
Au and 6 g/t Au, including a breccia with 1.2m @ 20.4 g/t Au and 81
g/t Ag.
-- Twenty-six holes for 3,100m are planned over these two target areas
in stage one.
-- Vieja Herradura target covers a 200 x 250m area northwest of Calandria
Sur with potential for extensions to the main breccia-hosted deposit and
also high-grade mineralisation proximal to the andestite dyke swarms
(CSD253 0.5m @ 141 g/t Au 237 g/t Ag) which may be a feeder zone for
Calandria Sur.
-- Other targets include extensions of the La Morena and La Calandria vein-
breccias at Calandria Norte, the new El Clavo Vein Trend to the south-
southwest of Calandria Norte, the Nido Este dome margin, and follow up
drilling at the Nido Norte target.
Commenting today, Chairman John Horsburgh said, 'The scale of our flagship Las Calandrias project continues to expand and a major breakthrough is the prospectivity of the volcaniclastics adjacent to the Calandria Sur dome-hosted gold-silver mineralisation. This is supported by encouraging results from lag sampling, mapping/rock chip sampling, trenching and limited previous drilling. Also, preliminary LeachWell tests indicate volcaniclastic-hosted sulphide mineralisation intersected to date is readily amenable to cyanide leaching. The recent work has opened up a very large target area close to Calandria Sur and, together with the new potentially high-grade targets, adds up to an exciting fourth drilling programme, the objective of which is to expand the recently established initial resource base.'
Drilling Programme
A minimum 10,000m programme of diamond drilling is planned with the first stage of 5,000m underway. The rig will then be deployed at the Company's Sierra Blanca silver-gold project also in Santa Cruz Province in October 2011 before returning for the second stage of follow up and exploratory drilling of targets at Las Calandrias, referred to below, at the end of October/November 2011. Assay results from the first stage of drilling will have been received by this time and will enable targets to be prioritised for stage two of the drilling programme.
Loma Verde/La Picasa target areas
Lag sampling, mapping, trenching and the limited previous drilling indicate potential for volcaniclastics adjacent to the northeast and east flank of the Calandria Sur rhyolite dome to host significant gold-silver mineralisation. This extensive target area is a northwest trending zone 200 to 300m wide by 500m long, subdivided into Loma Verde in the southeast and La Picasa to the northwest (Figure 3).
Mineralisation consists of multiple sub-metre zones of quartz veins/veinlets, breccias and stockworks related to broad zones of silicification trending west-northwest and east-northeast with individual silicified zones up to 25m x 350m. Rock chip sampling returned 1m @ 3.9 g/t Au (Loma Verde) and 0.5 m @ 11 g/t Au (La Picasa).
The rock chip sampling was carried out within a 1,000 x 500m area of mostly volcaniclastic terrain coinciding with the 30 ppb Au contour of an extensive lag anomaly (Figure 4). Anomalous gold in rock chips corresponds with a series of sub-metre veins, quartz stockworks and breccias. The average of 151 rock chip samples taken was 0.55 g/t Au and a maximum of 11 g/t Au with 11% of samples above 1 g/t Au. Sample locations and assay ranges are shown in Figure 3.
Best trench assays are 20m @ 1.0g/t Au (Loma Verde) and 20.8m @ 1.5g/t Au including 8.4m averaging 2.9g/t Au (La Picasa).
Two out of the three holes previously drilled in this area intersected moderate to high grade gold mineralisation in the volcaniclastics adjacent to the rhyolite dome. Hole CSD261 from the last drilling campaign (received too late for inclusion in the initial resource), drilled 50m away from the dome margin intersected multiple sulfide rich veinlets hosted by volcaniclastics assaying 35.5m @ 1.8 g/t Au and 6 g/t Ag, with a high-grade breccia of 1.2 m @ 20.4 g/t Au and 81 g/t Ag.
Twenty-six holes for 3,100m are planned for these two target areas in the first stage (Figures 2 & 3).
Calandria Sur - La Vieja Herradura target area
The last drill results from the third campaign confirm the mineralisation is open to the north and northwest of the Calandria Sur dome, outside the initial resource area. Recent mapping and rock chip sampling have defined a new 200 x 250m target area along this covered northern margin of the Calandria Sur dome, previously considered low priority (Figure 3).
Intersections of high-grade gold mineralisation in the last campaign are associated with a northwest trending post-mineralisation andesite dyke swarm that may have intruded along pre-existing mineralising 'feeders'. These dykes continue southeast along the margin of the Calandria Sur dome and might be a vector for high-grade mineralisation. Holes CSD253 (0.5m @ 140.8 g/t Au and 237 g/t Ag) and CSD255 (0.5m @ 16.9 g/t Au and 183 g/t Ag) are examples of high grades proximal to the dykes (Figure 3).
Approximately 1,080m of drilling in seven holes in the first stage is planned to extend mineralisation to the north-west of Calandria Sur and to test for high-grade mineralisation (Figure 2 & 3).
Calandria Norte dome - La Morena Vein-breccia
Scout hole CND250 previously intersected 0.6m @ 68.1 g /t Au and 107g /t Ag in a vein-breccia from 59m within a broad stockwork intercept of 19.5m @ 3.3g /t Au and 8g /t Ag from 45m. The vein-breccia system has no surface expression and was discovered by drilling the southwest end of an Induced Polarisation ('IP') chargeability anomaly. Limited drilling indicates that La Morena vein-breccia mineralisation strikes north-northeast for 350m, dips steeply south-southeast and is open in all directions. Further drilling at La Morena will target extensions and also the possible intersection with the La Calandria Vein Zone at depth. A total of 2,100m of drilling has been planned to test La Morena and other Calandria Norte targets with four holes for 500m at La Morena in the first stage.
El Clavo Vein Trend
Mapping, trenching, and rock and lag sampling southwest of the Calandria Norte dome has discovered the El Clavo vein trend, a possible southwest extension of the La Calandria Vein-breccia at the Calandria Norte target area into the surrounding volcaniclastics. Zones of vein-style silicification occur along a 550m strike, with rock chips from initial sampling assaying between 0.2 and 1.4g/t Au. A total of 700m of drilling is planned with two 100m holes in the first stage (Figure 2).
Nido Este
Nido Este is a northeast trending rhyolite dome 1.1km north-west of Calandria Sur. Two earlier holes (NED 47 and 48) testing a 3D chargeability IP anomaly intersected wide zones of disseminated and veinlet pyrite-marcasite mineralisation, but with no significant gold and silver values. However, recent lag and float rock-chip sampling (up to 16.4g/t Au) has located a new target 300m east of the drill-tested area, possibly related to north-east trending veins. Six holes totalling 1,000m are planned for the second stage (Figure 2).
Nido Norte
The Nido Norte target is located 2km north-west of Calandria Sur. The mineralisation associated with rhyolitic domes shows low-sulfidation epithermal features (chalcedonic quartz) along the 1.5km NE-SW trending La Despreciada vein-breccia structure. Mineralisation has both structural and lithological controls with drill intersections such as 26.3m @1g/t Au and 8g/t Ag including 1.6m averaging 5.2g/t Au and 71g/t Ag on the structure, as well as 0.75m averaging 8g/t Au and 54g/t Ag on lithologic contacts close to the main structure. Six holes totalling 1,000m will follow up these intersections in the second stage.
Las Calandrias Project Background
Las Calandrias comprises multiple zones of gold mineralisation hosted by rhyolite domes over a 10.5 sq km area. In 2009, the first drilling programme (September-October) consisted of 16 scout holes (1,566m) testing the Calandria Norte vein-breccia and Calandria Sur dome breccia targets where significant gold mineralisation was discovered. The second drilling programme (March-April 2010) consisted of 4,400m in 37 holes and tested Calandria Sur (28 holes/3,212m); Calandria Norte (2 holes/299m), El Nido Este (2 holes/309m) and El Nido Norte (5 holes/580m). Phase three drilling (September-December 2010) consisted of 14,003m in 110 holes; Calandria Sur (56 holes/6,186m); Calandria Norte (43 holes/6,175m); Nido Norte (7 holes/1,054m); Nido Oeste (2 holes/421m); La Herradura (2 holes/168m). The continuity of phase three (January-April 2011) consisted of 15,736 m in 90 holes; Calandria Sur (6 holes/2,747m); Calandria Norte (21 holes/3,430); Despreciada: Nido Norte and Nido Centro (37 holes/6,414m); Nido Oeste (7 holes/1,130m); Nido Sur (18 holes/1,883 m); Gamekeeper (1 hole/132 m).
The full document including the Figures 1 to 4 referred to in this announcement can be found at http://www.marianaresources.com/pdf/2011/110823_Mariana_news.pdf.
Details of the recent initial resource estimates for Calandria Sur and La Calandria can be found at http://www.marianaresources.com/news/2011.php.
The fourth drilling programme is being undertaken by ECOMINERA. The drill programme is directed by the Argentina Exploration Manager, Dr Gustavo Rodriguez (MAIG) under supervision of Executive Chairman Mr John Horsburgh. Exploration information in this announcement has been compiled by John Horsburgh who is a Fellow of the Australasian Institute of Mining and Metallurgy. Mr Horsburgh has sufficient experience relevant to the style of mineralization and types of gold deposit under consideration and to the activity that he is undertaking to qualify as a Competent Person as defined in the JORC Code. Mr. Horsburgh is a qualified person within the meaning of national Instrument 43-101.
Quality Assurance/Quality Control
All technical information for the Company's Argentina projects is obtained and reported under a quality assurance and quality control (QA/QC) program. All samples are collected under the supervision of the Company geologists and dispatched via commercial transport to ALS Chemex laboratories in Mendoza, Argentina, and assayed in Chile. ALS Chemex's quality system complies with the requirements for the International Standards ISO 9001:2000 and ISO 17025: 1999. Samples returning greater than 10 g/t gold and/or greater than 100 g/t silver are assayed using gravimetric analyses.
Systematic assaying of sample duplicates and commercially prepared standards and blanks is performed for analytical reliability.
For further information please visit website at www.marianaresources.com.
About Mariana Resources
Mariana Resources Ltd is an AIM and TSX quoted exploration and development company with an extensive portfolio of gold, silver and copper projects in Argentina and Chile. In southern Argentina, in addition to the Las Calandrias gold-silver discovery, the Company has the Sierra Blanca silver-gold prospect (70%); the Los Amigos joint venture (49%) with Hochschild Mining and a 160,000 Ha land package (100%) in the country. All of these projects are located in the Deseado Massif epithermal gold-silver district in mining-friendly Santa Cruz province of southern Argentina, which hosts four mines and several advanced projects. In Chile, Mariana has a joint venture with US based international mining and natural resources company Cliffs Natural Resources Inc., to explore for iron oxide-copper-gold deposits ('IOCG') in a 92,000 km2 area ('SCM Mariana Area') in north-central Chile along the highly prospective Atacama Fault Zone. The SCM Mariana Area includes the 44km2 Buenaventura and 46km2 Perro Chico IOCG projects. Mariana is also evaluating a number of gold-silver and copper-gold opportunities away from the Cliffs JV area, as part of a new initiative.
Safe Harbour
This press release presents 'forward-looking statements' within the meaning of Canadian securities legislation that involve inherent risks and uncertainties. Forward-looking statements include, but are not limited to, statements with respect to the future price of gold and other minerals and metals, the estimation of mineral resources, the capital expenditures, costs and timing of the resources, the realization of mineral reserve estimates, the capital expenditures, costs and timing of the development of new deposits, success of exploration activities, permitting time lines, currency exchange rate fluctuations, requirements for additional capital, government regulation of mining operations, environmental risks, unanticipated reclamation expenses, title disputes or claims and limitations on insurance coverage. Generally, these forward-looking statements can be identified by the use of forward looking terminology such as 'plans', 'expects' or 'does not expect', 'is expected', 'budget', 'scheduled', 'estimates', 'forecasts', 'intends', 'anticipates' or 'does not anticipate', or 'believes', or variations of such words and phrases or state that certain actions, events or results 'may', 'could', 'would', 'might' or 'will be taken', 'occur' or 'be achieved'.
Forward-looking statements are subject to known and unknown risks, uncertainties and other factors that may cause the actual results, level of activity, performance or achievements of Mariana to be materially different from those expressed or implied by such forward looking statements, including but not limited to: risks related to international operations, actual results of current exploration activities; actual results of current or future reclamation activities; conclusions of economic evaluations; changes in project parameters as plans continue to be refined; future prices of gold and other minerals and metals; possible variations in ore reserves, grade or recovery rates; failure of equipment or processes to operate as anticipated; accidents, labour disputes and other risks of the mining industry; and delays in obtaining governmental approvals or financing or in the completion of development or construction activities. Although the management of Mariana believes that the expectations reflected in such forward-looking statements are based upon reasonable assumptions and have attempted to identify important factors that could cause actual results to differ materially from those contained in forward-looking statements, there may be other factors that cause results not to be as anticipated, estimated or intended. There can be no assurance that such statements will prove to be accurate, as actual results and future events could differ materially from those anticipated in such statements. Accordingly, readers should not place undue reliance on forward-looking statements. Mariana Resources does not undertake to update any forward-looking statements that are incorporated by reference herein, except in accordance with applicable securities laws.
Neither the TSX nor its Regulation Services Provider (as that term is defined in the policies of the TSX Exchange) accepts responsibility for the adequacy or accuracy of this news release.
Contacts:
Mariana Resources Ltd.
John Horsburgh
Chairman
61 2 94374588
Mariana Resources Ltd.
Glen Parsons
CFO
61 2 94374588
Mariana Resources Ltd. (Vancouver Office)
Kathryn Witter
1 604 669 9336
www.marianaresources.com
RFC Corporate Finance Limited (Nomad)
Rob Adamson
61 2 9250 0041
RFC Corporate Finance Limited (Nomad)
Will Souter
61 2 9250 0050
FinnCap (Broker)
Matthew Robinson
44 20 7600 1658
Fox Davies Capital ( Co UK Broker)
Jonathan Evans
44 20 3463 5000
St Brides Media and Finance Ltd (PR)
Felicity Edwards
44 20 7236 1177
St Brides Media and Finance Ltd (PR)
Hugo de Salis
44 20 7236 1177