The La Paloma project, comprising 20 contiguous concessions totalling 56,600 hectares, is located in Santa Cruz Province, Argentina, near the north-western margin of the Deseado Massif, a Jurassic Age felsic volcanic province that hosts world class epithermal gold-silver mineralisation. The 100% owned project is located approximately 20 kilometres west of Goldcorp’s Cerro Negro Au-Ag project and 30 kilometres southwest of the San Jose Au-Ag project owned by Hochschild Mining Argentina and McEwen Mining Inc.
- 100% Patagonia Gold S.A.
- Hosts the Lomada de Leiva deposit, recently exploited by Patagonia Gold SA
- 56,600 ha property of which less than 10% has been subjected to any exploration
- Located 25 km WNW of Goldcorp’s Cerro Negro project and associated with the same caldera structure
- Hosts Brecha Sofia prospect with bonanza grade low-sulfidation Au-Ag mineralisation, including 3.0 m at 140.61 ppm Au and 419.7 ppm Ag
- Hosts the poorly exposed Cerro Vasco prospect where rock chip samples up to 44.2 ppm Au have been reported.
Geology and Mineralisation
The geology of the project area comprises a thick sequence of subhorizontal felsic pyroclastic deposits intruded by rhyolitic flow-dome complexes of the Jurassic aged Chon Aike Formation. Low sulfidation gold +/- silver mineralisation is hosted within steeply dipping quartz veins, breccias and stockworks within argillic and silicic alteration halos. Quaternary fluvio-glacial deposits and basaltic flows partially obscure the Jurassic volcanics.
At the Lomada de Leiva deposit, oxide gold mineralisation is localised in the near surface by a north-northeast trending, steeply east dipping structural corridor containing brecciated and variably silicified volcanic and tuffaceous rocks which have been cut by a network of fine anastomosing quartz veins and veinlets. The deeply oxidised breccia also contains clasts of chalcedonic quartz vein material. Gold is predominantly hosted in the kaolinised fault breccia matrix but is also reporting in the vein quartz and earlier chalcedonic veins over combined widths up to 30 m and along a strike length of approximately 700 m.
At the Brecha Sofia prospect, located 1 kilometre northeast of Lomada de Leiva, subvertical, tabular, low-sulfidation gold-silver bearing hydrothermal quartz breccias are hosted predominantly within a rhyodacitic dome complex.
At the Cerro Vasco prospect located at the northern end of La Paloma block, hydrothermal breccias associated with a dome complex to the north of the prospect host strongly elevated gold values and there is evidence of high-sulfidation style, gold-silver +/- Cu-Pb mineralisation elsewhere on the property.
Work to Date
Lomada de Leiva: Systematic geochemistry, geophysics and drilling was completed by Barrick Gold Corporation and Patagonia Gold S.A. culminating in an Indicated Resource of 5.0Mt at 1.0 g/t Au. This has now been largely exploited via open pit mining with heap leach recovery of the gold and the operation was terminated during 2016.
Breccia Sofia: Barrick Gold Corporation conducted geochemical and geophysical surveys, followed by trenching and diamond drilling at the prospect during 2004-5 and Patagonia Gold S.A. continued with exploration work after acquiring the project in 2007. 57 holes for a total of 12,000 m have been drilled to date.
Significant intersections include:
- DDH-LP42, 3.0 m at 140.6 ppm Au and 419.7 ppm Ag from 272.5 m
- DDH-LP47, 3.15 m at 13.05 ppm Au and 38.4 ppm Ag from 279.9 m
- DDH-LP51, 10.0 m at 4.99 ppm Au and 0.7 ppm Ag from 251.7 m
- BSRD-002, 1.0 m at 32.00 ppm Au and 33.0 ppm Ag from 320.0 m
- BSR-015, 4.0 m at 17.3 ppm Au and 3.2 ppm Ag from 48.0 m
Cerro Vasco: Three shallow RC holes were drilled by Mincorp in 1997 at Brecha La Emilia; however, it is unclear whether the holes effectively tested the structure. Geological mapping, trenching, IP geophysics and ground magnetics have been completed by Patagonia Gold S.A since 2013. Rock chip and float samples have reported high grade gold concentrations from rock chip, float and trench sampling. RC drilling is proposed to test beneath the cover sequences.
Brecha Sofia: High grade quartz breccia hosted low-sulfidation epithermal gold +/- silver mineralisation.
Cerro Vasco: Good potential for low, or high-sulfidation epithermal gold-silver mineralisation beneath thin Quaternary cover sequences.