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Condor Gold reports final results for 43 drill hole program at La India Project in Nicaragua

Published 06 November 2017

Condor Gold has announced the final six drill hole results from a 43 drill hole program on the Mestiza Vein Set (‘Mestiza’) at the La India Project, Nicaragua.

A drill programme of 5,922 metres was completed in August with the initial focus on the Tatiana Vein, one of the four constituent veins at Mestiza, along with the nearby Buenos Aires and Jícaro veins. The objective was to convert the upper part of a historic Soviet mineral resource (2,392,000 tonnes at 10.2 grams per tonne (“g/t”) gold for 785,694 ounces of gold) to Canadian NI 43-101 standard however this has now also developed into allowing Condor to better understand the extent of the mineralisation and further resource potential at Mestiza, which is open along strike beyond the Soviet resource. It is now considered that drilling below 200m, as further detailed below, is required to determine the volume of the historic Soviet resource that can be converted to NI 43-101 standard.

Highlights:

  • 5,922 metres completed, with drilling restricted to the top 200 metres (below ground surface), which demonstrates excellent continuity of the structures, high-grade ore from surface, and open pit potential
  • A high-grade oreshoot (‘Big Bend’) on the Tatiana vein is defined over a strike length of 450 metres and depth of 200 metres. It has mineralised true widths up to 4.6 metres (averaging 2.2 metres over the main mineralised section), in addition to a hanging wall vein up to 6.1 metres true width (averaging 1.0 metre)
  • Best results received from the final six drill holes (totalling 850 metres) include:

          - LIDC378 drill width 0.50 metres (true width 0.4 metres) at 17.4 g/t gold and 3.0 g/t silver from 77.30 metres downhole depth.

          - LIDC383 drill width 1.40 metres (true width 1.1 metres) at 18.50 g/t gold and 22.1 g/t silver from 19.60 metre.

  • Mapping and trenching continues on the extensions along strike of the constituent veins on Mestiza

Mark Child, Chairman and CEO comments: “The final six drill holes of a 43 drill hole programme, totalling about 6,000 metres, at Mestiza demonstrate high grade gold mineralisation from surface to a depth of up to 200 m beneath surface.

“The discovery of a high-grade oreshoot (‘Big Bend’) on the Tatiana vein, which has a strike length of 450 metres, an estimated average true width of 2.2 metres and a depth of at least 200 metres, is material to the Project. Additionally, there is potential for a small open pit on the Tatiana vein that can add high grade gold to the mine plan, reduce the payback period and enhance the project economics.

“On one section line in Big Bend, LIDC383 intersects the vein 20 metres beneath surface and has a drill width of 1.40 metres at 18.50 g/t gold. From previously reported drilling on the same section: LIDC 344 (80 metres beneath surface) has a drill width of 3.30 metres at 28.3 g/t gold; LIDC 358 (160 metres beneath surface) has a drill width of 3.55 metres at 23.3 g/t gold.

“Finally, as Condor has only drilled to a depth of up to 200 metres beneath surface, there is further potential in the lower half of the historic Russian resource, which was up to a depth of approximately 500 metres and remains untested.”

Background

The La India Project’s existing NI 43-101-compliant mineral resource includes 9.6 Mt at 3.5 g/t gold for 1,083,000 oz gold in the Indicated mineral resource category and 8.5 Mt at 4.5 g/t gold for 1,231,000 oz gold in the Inferred mineral resource category. This consists of seven separate resources, most of them open along strike and at depth. It includes Mestiza, which hosts a NI 43- 101-compliant Inferred mineral resource of 1,490 kt at 7.47 g/t for 333,000 oz gold. Here, Sovietbacked drilling in 1991 led to a Soviet-style mineral resource estimate of 2,392 kt at 10.2 g/t gold for 785,694 oz gold. The bulk of the resources are contained within the Tatiana vein, the largest of the four main veins at Mestiza, which also includes the Buenos Aires and Jicaro veins to the north, and Espinito vein set to the west, of Tatiana.

Mestiza Drill Plan

Condor commenced drilling with one rig on the 23 rd March 2017, to test the Soviet drilling and convert the top half of the Soviet mineral resource to Canadian NI 43-101 standard. The first batch of assays was reported on the 22nd May 2017. A second rig was introduced and the second batch of assays was reported on the 29th June 2017.

This initial programme finished in August 2017, with the completion of 43 drill holes for 5,922 m in total.The best intercepts above 20 g/tm (grade x thickness) gold (Au) for the entire drill programme. Results for last six drill holes from LIDC378 to 383 are presented. The drill plan shows the distribution of these holes.

Drilling with large diameter (PQ) core was a priority because it provided high recoveries and larger sample sizes. The drill rigs have achieved this, but have only been able to test the top 200 m. It is now considered that deeper holes are required to fully test the volume of the historic Soviet resource, which extends to approximately 500 m beneath surface. This will require more powerful rigs. Drill results for last six drill holes New drill results (from holes LIDC378 to 383) are shown. The drill plan shows the distribution of these holes.

Discussion of Drill Results

Mineralisation occurs within a 4.0 to 6.0 m-wide mineralised structure cutting a major unit of welded tuff with conspicuous fiamme. The structure consists of:

  • An early-stage broad zone of jigsaw and crackle hydrothermal breccia with drusy and comb vein quartz in the matrix. These support angular clasts of weakly silicified wall rock. This phase normally has low gold grade.
  • A central high-grade quartz vein, typically 0.5-1.0 m wide, with comb and drusy quartz and minor chalcedony. Textures vary between holes, from massive silica to local colloform, pale green chalcedony with fine streaks of sulphides and leaching textures (moulds after calcite).
  • Late fault breccias with vein clasts and hydrothermal breccia in a sooty, black, manganiferous gouge and brick red smectite. These frequently contain high grade gold.

Gold mineralisation is associated with the quartz vein and fault breccia over true widths of up to 3.0 m. The nature of the fault breccia, with variable amounts of gold-mineralised vein clasts in clay gouge, leads to high gold grade variability. Drilling with PQ core is preferred to maximise the sample size.

There is also a possible supergene enrichment effect, suggested by increased silver in some deeper holes (e.g. 0.7 m at 356 g/t Ag from 198.1 m in LIDC030B).

A long section of the Tatiana vein plots the drill hole intercepts where they and intersect the vein. It shows all historic and new drilling. Each point is coloured according to average grade and sized according to the grade x thickness factor, which is the downhole intercept length multiplied by the gold grade. At the local scale, this shows the highly variable nature of mineralisation, with narrow low-grade intersections only metres away from wide high-grade intersections. At the larger scale, the long section shows that the vein is broadly well mineralised and forms high grade shoots separated by intervening areas of low grade where the mineralised zone is thinner.

A geological model has been developed which correlates high grade gold mineralisation with bends in the vein. These bends created more open space, allowing more hydrothermal fluid circulation, resulting in higher grade. Big Bend, which appears to pitch steeply west, has a strike of approximately 450 m.

The deepest drill holes, about 200 m below surface, intersected lower grades and/or narrower veins. This may reflect pinching of the vein or the base of the oxide zone and supergene enrichment. However, this has only been tested in two holes at the western end of Big Bend: LIDC361, which returned a disappointing 0.25 m at 1.05 g/t Au, intersected a 3.35 m-wide (downhole) vein and fault breccia zone in HQ core. Deeper drilling is needed to test the extension of the high-grade zone.

Mapping at Mestiza

Detailed mapping was initiated at Mestiza to better understand the geometry of the veins and identify new bends that may merit drill testing. Mapping has traced epithermal quartz veins over a strike length of at least 3.5 km at Mestiza. The Tatiana, Jícaro and Buenos Aires veins coalesce in the northwest and seem to combine into a northwest-striking vein. There is also a newly discovered, parallel vein, the Tortuga Vein, which assayed up to 6.1 g/t Au in a mullock sample. Historic sampling of the northwestern extension of all these veins includes 47.7 g/t Au over 0.2 m, at 450 m along strike from the westernmost Tatiana vein exposures.

Rock chip sampling and trenching has commenced on the northwest extensions of veins within the enlarged Mestiza vein set, to generate drill targets.

Mestiza in the context of La India

Mestiza is significant for five reasons:

  • It already hosts a NI 43-101-compliant Inferred mineral resource of 1,490 kt at 7.47 g/t; 333,000 oz gold. However, a Soviet mineral resource of 2,392 kt at 10.2 g/t gold for 785,694 oz gold was previously defined and an opportunity exists to upgrade the former. This is excluded from the current Pre-Feasibility Study (“PFS”) and Preliminary Economic Assessment (“PEA”) at La India.
  • The PEA (December 2014) has an open pit and underground mining scenario using a 1.6 Mtpa processing plant recovering 1,203 koz gold over the life of mine, with the first five years production averaging 138,000 oz gold pa.
  • The January 2016 Whittle Enterprise Optimisation to NPV of the above PEA materially increased the recovered gold and project economics. Using the same 1.6 Mtpa processing plant, recovered gold increased to 1,437 koz gold over the life of mine, with the first five years of production averaging 165,000 oz gold pa.
  • All production scenarios exclude Mestiza, which is in close proximity to La India. There is excellent potential to bring high grade gold from Mestiza into a future mine plan, feeding a centralised processing plant.
  • Importantly, Mestiza hosts a shallow, high-grade, oxidised resource. This is currently viewed as a combined open pit-underground mining target. The average drill depth is 112 m for the 6,000 m resource conversion drilling programme. The existing resource is open along strike in both directions and at depth. Its shallow, high grade nature suggests it could be added early on to the mine plan, enhancing the production profile and economics of the project.


Source: Company Press Release