- Tech Reports
Santa Ana covers the core of the historic Mariquita Silver District, one of Colombia's most prolific colonial silver mining camps with production dating back to the sixteenth century. Santa Ana comprises 669 hectares of the historic Mariquita Silver District, one of Colombia's most prolific colonial silver mining camps with production dating back to the sixteenth century. The property is located approximately 190 kilometres ENE of Bogota in Tolima, Colombia.
A NI 43-101 Technical Report on the Santa Ana Property dated April, 2013, coauthored by Doublewood Consulting Inc. and Antediluvial Consulting Inc., cited the following archival information from historical Spanish documents regarding past production at Santa Ana:
"The La Porfia, El Dorado, La Manta and La Obdulia mines are located within the property as part of the historic colonial Santa Ana silver mines. The average smelter return for silver ore during those days was "4 marcos per quintal" (approximately 17 kg/t Ag) according to official reports of Hacienda Santa Fe (year 1585) also reporting widths exceeding 1 1/2 varas (4 1/2 feet). More veins were discovered in the Santa Ana (today Falan) and Frias region following exploration during the XVI Century, adding 14 new mines to the district, all of them producing over 1 marco of silver per quintal (approximately 4.3 kg/t Ag)."
The Santa Ana property is located on the eastern side of the Central Cordillera, underlain by highly deformed Paleozoic schists, quartzites and gneisses of the Cajamarca formation, intruded by the Tertiary El Hatillo granodiorite stock. The polymetallic silver-gold veins are characteristic of an intrusion related silver rich system later overprinted by a low sulphidation epithermal system in a thrust and fold setting. They are comprised of variable amounts of pyrite, sphalerite, galena, silver sulphosalts, native silver and gold in a gangue of quartz and adularia. The veins generally strike N-S to NNE and dip 45 to 85 degrees W to NW. They are directly related to right-lateral strike-slip movement on the regional scale Palestina Fault System.
Preliminary prospecting, rock chip sampling, and drilling were carried out by Condor between 2012 and 2014. Chip samples of vein material collected in 2012 from the historic Santa Ana mine tunnels returned assay values as high as 11 g/t Au and 2,820 g/t Ag. Other high silver values included 929 g/t Ag, 600 g/t Ag and 443 g/t Ag. Chip samples collected from outcrops in 2013-2014 returned several high gold values along with high silver values, including: 68 g/t Au and 422 g/t Ag; 48 g/t Au and 81 g/t Ag; and 36 g/t Au and 163 g/t Ag.
A preliminary diamond drilling programme was conducted in 2012 completing eight shallow holes for a total of 1,170 metres. All of the holes were drilled from a single platform and tested the down-dip extension of vein mineralization below the historic Santa Ana mine tunnels. The results further highlighted the potential for bonanza-type silver-gold veins, with drill intersections including: 1,751 g/t (51 oz/t) AgEq over 3.04 metres; 1,465 g/t (43 oz/t) AgEq over 1.82 metres; and 2,545 g/t (75 oz/t) AgEq over 1.34 metres.
Table 1: Santa Ana Drill Intersections
|Hole||From (m)||To (m)||Length (m)||Au (g/t)||Ag (g/t)||AgEq (g/t)|