COPPER-GOLD EXPLORATION & DEVELOPMENT IN SOUTH AMERICA
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El Desesperado
RC Hole CED-R-4 (blue casing)
Drilling to Add Another "Star" to the Toki Cluster
Highlights
In November 2012, the Company announced assay results from the 8 hole 2,308m reverse circulation (RC) drilling program completed at its El Desesperado copper project in the Chuquicamata district and located 7 km NW of the city of Calama in the II Region of Chile, and immediately west of Codelco's Toki Cluster deposits.
RC holes CED-R-1 to 5 were completed in the El D Norte target and CED-R-6 to 8 in the El D Sur target. Assay results are shown on Table 1, with drill hole locations shown on Figure 1.
Table 1; El Desesperado Significant Intersections
For more details of the drill results, refer to the Company's News Release 12-18, dated November 22, 2012 available at: link to November 22, 2012 12-18 News Release.
The Company was pleased with the results of CED-R-4, the first recorded mineralized hole ever drilled on the property, which intersected a partially oxidized chalcocite enrichment blanket essentially from surface to the bottom of the hole. Coro achieved its objective with this initial drill program which was to demonstrate the presence of a porphyry copper system within the very large prospective area identified from its surface work, and intersect ore grade mineralization in at least one of the holes. The presence of attractive grades and thicknesses in CED-R-4 together with remnant copper oxides and anomalous leached cap assays in holes CED-R-1, 2 & 5, as well as the Company's sampling and mapping, indicate that the El D Norte target has potential to host a significant porphyry copper deposit. The El D Sur results, while not intersecting ore grades, confirm the presence of remnant copper oxides in the leach cap, chalcocite coating and primary sulphides in the pyrite-chalcopyrite zone, in an area with very poor outcrop. The Company intends to conduct a follow up diamond drilling program in the first half of 2013 to further test both targets.
As described in the Company's news release of November 1st 2012, the drill program was designed to provide an initial test of an ~ 4km2 prospective area of porphyry copper style alteration and anomalous copper geochemistry resulting from Coro's mapping and sampling program completed earlier this year. Inclined holes CED-R-1 and 5 intersected tonalite porphyry in anomalous leached cap before passing into propylitically altered wall rock diorite and a late stage phaneritic diorite intrusive, while inclined hole CED-R-2 was drilled entirely in tonalite porphyry and hydrothermal breccia within the leached cap, prematurely terminating in a fault zone. Inclined hole CED-R-3 tested an area of leached cap some 750m ENE of the other holes, intersected a short interval of leached tonalite porphyry before entering propylitically altered wall rock diorite over most of the rest of the hole and encountered increasing amounts of chalcopyrite associated with sericite in the last 8m of the hole. Vertical hole CED-R-4 was drilled entirely in tonalite porphyry and hydrothermal breccia; mineralization was mostly disseminated and veinlet chalcocite, partially oxidized and leached until the last 16m of the hole where both chalcocite and chalcopyrite are present. Holes CED-R-6 and 7 intersected anomalous leached cap with remnant copper oxides, thin chalcocite coatings on pyrite and increasing amounts of chalcopyrite with depth, while CED-R-8 intersected anomalous leached cap before entering a post mineral granodiorite.
About El Desesperado
Coro believes there is good potential on the El Desesperado property to host mineralization of similar style to the adjacent Toki Cluster deposits (Toki, Quetena, Genoveva, Opache, Miranda and Pulucktur). These are associated with swarms of NNE oriented Eocene age porphyry dykes and stocks, intruded into both Paleozoic volcanics and precursor Tertiary plutons. Zones of copper mineralization associated with potassic alteration are related to the porphyries with higher copper grades occurring where this has been overprinted by sericite alteration, or where later veining is present. The deposits tend to have very sharp boundaries between mineralization and barren rock. The Toki Cluster deposits have been oxidized to depths in excess of 100m beneath the gravel cover which overly all of them, and host major copper oxide resources, as well as significant underlying primary sulphide mineralization, and in the case of Opache and Pulucktur, secondary enrichment blankets. Codelco has not published resource estimates for these deposits, but information in academic papers quotes inferred resources for the Cluster of approximately 20 Mt of contained copper, with Toki hosting 9.1 Mt, Quetena 5.0 Mt and Opache 1.2 Mt, at grades of approximately 0.5% Cu.
El D Norte is located at higher elevations than the nearby Genoveva, Quetena and Toki deposits, and has a higher level phylllic alteration suite preserved. El D Sur is a large area of poor outcrop, mostly covered with thin overburden and scree; outcrops are of phyllic alteration bordered by propylitic alteration to the SW.
Small scale open pit mining and leaching of copper oxide bearing breccias, took place at the old Quetena Mine on the property during the 1960-70's, and it was subsequently explored by two major mining companies, firstly in 1997-98 prior to the discovery of the Toki Cluster; and secondly in 2004. The first company completed wide spaced reverse circulation and diamond drilling (11 holes, 2,582m), mostly aimed at testing geophysical targets, while the second company completed vertical reverse circulation drilling (2 holes, 700m) which tested two conceptual targets. In neither case, was significant mineralization intersected.
In December 2011, Codelco initiated the permitting process for production of cathode copper from the combined Quetena and Genoveva deposits. According to the publicly available Environmental Impact Study, this will involve an open pit at each of the deposits, the trucking of 30,000tpd of higher grade ore to the existing SXEW facilities at Chuquicamata, and 60,000tpd of Run of Mine dump leaching at the project site, followed by pumping of solution to Chuquicamata. Planned production is 528,000 tonnes of cathode copper over the 10 year life of the project, with an average production of 62,000 tpy Cu in the first five years. Capital investment is estimated to be US$244,000,000.
Genoveva is located ~1km E of the El Desesperado property, Opache ~2km to the ESE, and Pulucktur, ~1.5km to the SSW
Figure 1: El Desesperado Location, showing Coro claim block in blue, Toki Cluster deposits in black hachured lines, Coro RC holes in red, old holes in black, prospective area in green, target areas in pink, faults in blue.
El Desesperado Option Terms (February 2012)
Coro may acquire 100% of the El Desesperado property for a total of US$13,000,000 by making the following staged option payments;
On signing: US$200,000 (paid)
12 months from signing: US$500,000
24 months from signing: US$1,300,000
36 months from signing: US$3,000,000
48 months from signing: US$8,000,000
In addition, a 1.9% sales royalty is payable on any production from the property, over which Coro has a first right of refusal.
Drilling to Add Another "Star" to the Toki Cluster
Highlights
- November 2012 drill results included RC Hole CED-R-4, 204m @ 0.55% CuT, bottomed in greater than 1%CuT; potential to host a significant porphyry copper deposit.
- CED-R-4 intersected a partially oxidized chalcocite enrichment blanket essentially from surface to bottom of hole
- Follow-up diamond drilling in H1 2013 on El D Norte and El D Sur targets
- Adjacent to Codelco's Toki Cluster of 5 major deposits, each of which contains several hundred million tonnes of mineralization at 0.4-0.5% Cu
In November 2012, the Company announced assay results from the 8 hole 2,308m reverse circulation (RC) drilling program completed at its El Desesperado copper project in the Chuquicamata district and located 7 km NW of the city of Calama in the II Region of Chile, and immediately west of Codelco's Toki Cluster deposits.
RC holes CED-R-1 to 5 were completed in the El D Norte target and CED-R-6 to 8 in the El D Sur target. Assay results are shown on Table 1, with drill hole locations shown on Figure 1.
Table 1; El Desesperado Significant Intersections
Target |
Hole |
From |
To |
m |
%CuT |
Type |
|---|---|---|---|---|---|---|
El D Norte |
CED-R-1 |
2 |
40 |
38 |
0.14 |
Cu Ox |
CED-R-2 |
Anomalous leach cap |
|||||
CED-R-3 |
No significant results |
|||||
CED-R-4 |
0 |
204 |
204 |
0.55 |
Mixed |
|
inc |
4 |
92 |
88 |
0.71 |
" |
|
and |
110 |
172 |
62 |
0.24 |
" |
|
and |
172 |
204 |
32 |
0.99 |
" |
|
inc |
198 |
204 |
6 |
1.94 |
" |
|
CED-R-5 |
Anomalous leach cap |
|||||
El D Sur |
CED-R-6 |
72 |
90 |
18 |
0.16 |
Cu Ox |
CED-R-7 |
120 |
144 |
24 |
0.14 |
Chalcocite coating |
|
and |
164 |
190 |
26 |
0.18 |
Primary |
|
CED-R-8 |
Anomalous leach cap |
|||||
For more details of the drill results, refer to the Company's News Release 12-18, dated November 22, 2012 available at: link to November 22, 2012 12-18 News Release.
The Company was pleased with the results of CED-R-4, the first recorded mineralized hole ever drilled on the property, which intersected a partially oxidized chalcocite enrichment blanket essentially from surface to the bottom of the hole. Coro achieved its objective with this initial drill program which was to demonstrate the presence of a porphyry copper system within the very large prospective area identified from its surface work, and intersect ore grade mineralization in at least one of the holes. The presence of attractive grades and thicknesses in CED-R-4 together with remnant copper oxides and anomalous leached cap assays in holes CED-R-1, 2 & 5, as well as the Company's sampling and mapping, indicate that the El D Norte target has potential to host a significant porphyry copper deposit. The El D Sur results, while not intersecting ore grades, confirm the presence of remnant copper oxides in the leach cap, chalcocite coating and primary sulphides in the pyrite-chalcopyrite zone, in an area with very poor outcrop. The Company intends to conduct a follow up diamond drilling program in the first half of 2013 to further test both targets.
As described in the Company's news release of November 1st 2012, the drill program was designed to provide an initial test of an ~ 4km2 prospective area of porphyry copper style alteration and anomalous copper geochemistry resulting from Coro's mapping and sampling program completed earlier this year. Inclined holes CED-R-1 and 5 intersected tonalite porphyry in anomalous leached cap before passing into propylitically altered wall rock diorite and a late stage phaneritic diorite intrusive, while inclined hole CED-R-2 was drilled entirely in tonalite porphyry and hydrothermal breccia within the leached cap, prematurely terminating in a fault zone. Inclined hole CED-R-3 tested an area of leached cap some 750m ENE of the other holes, intersected a short interval of leached tonalite porphyry before entering propylitically altered wall rock diorite over most of the rest of the hole and encountered increasing amounts of chalcopyrite associated with sericite in the last 8m of the hole. Vertical hole CED-R-4 was drilled entirely in tonalite porphyry and hydrothermal breccia; mineralization was mostly disseminated and veinlet chalcocite, partially oxidized and leached until the last 16m of the hole where both chalcocite and chalcopyrite are present. Holes CED-R-6 and 7 intersected anomalous leached cap with remnant copper oxides, thin chalcocite coatings on pyrite and increasing amounts of chalcopyrite with depth, while CED-R-8 intersected anomalous leached cap before entering a post mineral granodiorite.
About El Desesperado
Coro believes there is good potential on the El Desesperado property to host mineralization of similar style to the adjacent Toki Cluster deposits (Toki, Quetena, Genoveva, Opache, Miranda and Pulucktur). These are associated with swarms of NNE oriented Eocene age porphyry dykes and stocks, intruded into both Paleozoic volcanics and precursor Tertiary plutons. Zones of copper mineralization associated with potassic alteration are related to the porphyries with higher copper grades occurring where this has been overprinted by sericite alteration, or where later veining is present. The deposits tend to have very sharp boundaries between mineralization and barren rock. The Toki Cluster deposits have been oxidized to depths in excess of 100m beneath the gravel cover which overly all of them, and host major copper oxide resources, as well as significant underlying primary sulphide mineralization, and in the case of Opache and Pulucktur, secondary enrichment blankets. Codelco has not published resource estimates for these deposits, but information in academic papers quotes inferred resources for the Cluster of approximately 20 Mt of contained copper, with Toki hosting 9.1 Mt, Quetena 5.0 Mt and Opache 1.2 Mt, at grades of approximately 0.5% Cu.
El D Norte is located at higher elevations than the nearby Genoveva, Quetena and Toki deposits, and has a higher level phylllic alteration suite preserved. El D Sur is a large area of poor outcrop, mostly covered with thin overburden and scree; outcrops are of phyllic alteration bordered by propylitic alteration to the SW.
Small scale open pit mining and leaching of copper oxide bearing breccias, took place at the old Quetena Mine on the property during the 1960-70's, and it was subsequently explored by two major mining companies, firstly in 1997-98 prior to the discovery of the Toki Cluster; and secondly in 2004. The first company completed wide spaced reverse circulation and diamond drilling (11 holes, 2,582m), mostly aimed at testing geophysical targets, while the second company completed vertical reverse circulation drilling (2 holes, 700m) which tested two conceptual targets. In neither case, was significant mineralization intersected.
In December 2011, Codelco initiated the permitting process for production of cathode copper from the combined Quetena and Genoveva deposits. According to the publicly available Environmental Impact Study, this will involve an open pit at each of the deposits, the trucking of 30,000tpd of higher grade ore to the existing SXEW facilities at Chuquicamata, and 60,000tpd of Run of Mine dump leaching at the project site, followed by pumping of solution to Chuquicamata. Planned production is 528,000 tonnes of cathode copper over the 10 year life of the project, with an average production of 62,000 tpy Cu in the first five years. Capital investment is estimated to be US$244,000,000.
Genoveva is located ~1km E of the El Desesperado property, Opache ~2km to the ESE, and Pulucktur, ~1.5km to the SSW
Figure 1: El Desesperado Location, showing Coro claim block in blue, Toki Cluster deposits in black hachured lines, Coro RC holes in red, old holes in black, prospective area in green, target areas in pink, faults in blue.
El Desesperado Option Terms (February 2012)
Coro may acquire 100% of the El Desesperado property for a total of US$13,000,000 by making the following staged option payments;
On signing: US$200,000 (paid)
12 months from signing: US$500,000
24 months from signing: US$1,300,000
36 months from signing: US$3,000,000
48 months from signing: US$8,000,000
In addition, a 1.9% sales royalty is payable on any production from the property, over which Coro has a first right of refusal.