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Chile - Region II-III - Simple Summary & IRN Projects 2
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May 2012 - Magallanes
Trench Sampling
Grab Samples
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Magallanes Property Summary
The Magallanes property covers approximately 127 hectares and is located along the Palaeocene-Eocene volcanic belt of northern Chile that hosts some of the most important precious metals and copper deposits in the country. The property is located about 45 kilometres due north of Yamana's important gold-silver mines at El Peñon and Fortuna, and just north of Yamana's recent Pampa Augusta Victoria discovery. The property is prospective for epithermal gold and silver mineralization of low sulphidation type.
Access to Magallanes is very good, with the property lying less than 10km from the main paved road that connects the giant Escondida copper mine to the northern Chilean coastal port town of Antofagasta. Total journey time from Antofagasta is about 1.5 hours.
Geological Setting of Magallanes
The Palaeocene to Early Eocene Volcanic Belt of northern Chile underlies much of the Atacama Desert in the Antofagasta and Atacama regions of northern Chile. The belt extends north-south for about 600km and is bounded to the west by the Coastal Cordillera and to the east by the Domeyko Cordillera. The geology of the belt is dominated by Late Cretaceous to Early Tertiary calc-alkaline to sub-alkaline bimodal volcanic rocks that range from basaltic andesite to rhyolite, and by sub-volcanic porphyritic intrusions and granitoid stocks.
The portion of the belt between Sierra Gorda in the north and Sierra Overa in the south, which includes Pampa Sur, is characterized by exposures of felsic volcanic rocks, and is host to several epithermal precious metal deposits including the El Peñon and Fortuna gold-silver mines, as well as other significant precious metal deposits at San Cristobal, Faride, El Soldado, Cachinal de la Sierra, El Guanaco, Amancaya and Sierra Overa.
Locally, the geology of the area around Magallanes comprises Carboniferous through Cretaceous age felsic volcanic sequences, volcano-sedimentary sequences, marine sediments, andesitic volcanics and red-bed sequences. Upper Cretaceous diorites and monzo-diorites intrude the overall sequence.
Work Completed To Date
The Magallanes property is centred on a small hill with a number of small, historically worked, artisanal mine workings. None of the workings have been entered by Iron Creek geologists, but the maximum depth of the workings is estimated to be of the order of 30m, and mostly much less. Overall tonnages exploited historically are minor.
Barrick carried out exploration in the early 2000s, including several short drill holes in and around the property.
Iron Creek has carried out detailed geological mapping of the property and vein structures, collected surface grab samples of vein material from old workings and outcrops, and carried out two phases of trenching with a back-hoe digger -- the latter during 2012.
A total of 113 one-metre measured samples were collected by Iron Creek in March 2012 from 24 short trenches cut in an attempt to cross the Veta Veinticinco at Magallanes, one of the principal known structures on the Magallanes property, at approximately 50m to 100m intervals along the currently known trace of the vein that extends for about 1km on Iron Creek's property. Additionally, a further 21 grab samples were collected from veins and abandoned workings.
Of the 24 trenches cut, only 7 were totally effective in cutting the vein structure, principally due to the difficulties in getting the mechanical back-hoe digger to appropriate locations due to steep slopes along the presumed strike of the Veinticinco vein structure, combined with the presence of colluvial cover and the presence of a volcanic ash horizon in some areas, neither of which allowed the back-hoe digger to penetrate through to bedrock along the interpreted trace of the vein structure in all cases.
Results to Date
All of the effective trenches cut anomalous gold and silver values in quartz vein material with 4 of the trenches cutting potential ore grade values of gold and/or silver, as follows:
| Trench Number |
Trench Sample Number |
Au ppm |
Ag ppm |
Rock Type |
| T3 |
C100988 |
0.639 |
7.7 |
Wall rock with argillic alteration |
| C100989 |
1.525 |
29.4 |
Quartz vein with manganese oxides |
| C100990 |
0.365 |
14.5 |
Wall rock with manganese & iron oxides |
| T5 |
C112954 |
0.008 |
2.2 |
Dacite |
| C112955 |
0.018 |
16.1 |
Fault with manganese oxides |
| C112956 |
0.02 |
12 |
Dacite |
| C112957 |
0.011 |
5.7 |
Dacite |
| T6 |
C112968 |
0.1 |
6.1 |
Fault |
| C112969 |
0.028 |
0.8 |
Dacite |
| C112970 |
0.05 |
<0.5 |
Fault |
| C112971 |
1.935 |
42.4 |
Quartz vein with manganese oxides |
| C112972 |
0.088 |
3.6 |
Dacite - faulted |
| C112973 |
0.037 |
0.7 |
Dacite - fractured |
| T10 |
C112979 |
9.72 |
61.1 |
Quartz vein with manganese oxides |
| C112980 |
0.949 |
4.9 |
Wall rock with manganese & iron oxides |
| C112981 |
0.038 |
2.4 |
Dacite |
| C112982 |
0.02 |
1.7 |
Fault |
| T13 |
C112984 |
0.03 |
1.2 |
Dacite |
| C112985 |
0.006 |
1.2 |
Dacite |
| C112986 |
0.032 |
1.5 |
Dacite |
| C112987 |
0.546 |
0.6 |
Fault with manganese oxides |
| T16 |
C112994 |
1.45 |
92.2 |
Quartz vein with manganese oxides |
| C112995 |
0.137 |
15.9 |
Wall rock with argillic alteration and quartz veining with manganese oxides |
| C112996 |
0.674 |
5.5 |
Quartz veinlets with manganese oxides |
| T17 |
C112997 |
0.034 |
2.1 |
Rhyolite |
| C112998 |
0.072 |
8.9 |
Quartz vein |
| C112999 |
0.022 |
2.2 |
Rhyolite |
All trench samples are 1m channel samples from along the side wall of the relevant back-hoe trench. Quartz vein samples may not represent true widths as some dilution may have occurred.
Additionally, several of the grab samples of quartz vein material from trenches gave highly anomalous results, with maximums of 18.0 g/t Au and 328 g/t Ag:
| Trench Number |
Grab Sample Number |
Au ppm |
Ag ppm |
Rock Type |
| T3 |
C100965 |
4.840 |
328.000 |
Quartz vein with manganese oxides |
| T5 |
C100964 |
0.265 |
19.900 |
Fault with manganese oxides |
| T6 |
C100963 |
5.130 |
64.900 |
Quartz vein with manganese oxides |
| T10 |
C100960 |
18.000 |
65.700 |
Quartz vein with manganese oxides |
| C100961 |
0.251 |
4.800 |
Wall rock with manganese & iron oxides |
| T16 |
C100959 |
1.06 |
23.8 |
Quartz vein with manganese oxides |
| T17 |
C100958 |
0.090 |
9.300 |
Quartz vein |
Many of the samples returning precious metals values have highly anomalous lead and zinc values, typically >>1,000 ppm, with lesser arsenic and antimony anomalies. All precious metals mineralised samples also returned highly anomalous manganese values, typically >>1,000 ppm.
Qualified Person
Demetrius Pohl, Certified Professional Geoscientist (CPG), is the Company's Qualified Person as defined by National Instrument 43-101, and is responsible for the accuracy of the technical information in this project summary.
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