[PRESSWIRE] Vancouver, British Columbia – January 24th 2023 – Terra Balcanica Resources Corp. (“Terra” or the “Company“) (CSE:TERA; FRA: UB1) is pleased to announce the discovery of a gold bearing system at Brezani within its 90% owned Viogor-Zanik project, Bosnia and Herzegovina.
- Another Viogor-Zanik discovery: the Brezani target maiden drillholes intercepted61 g/t AuEq over 88.0 m (BREDD002) and 0.58 g/t AuEq over 28.6 m (BREDD001); both drillholes encountered gold mineralization from surface confirming the extension of the 32 m at 0.54 g/t AuEq interval detected by trenching 65 m southeast of the drillhole collars (see Company news release from August 17th, 2022);
- Expanding district-scale polymetallic footprint: Viogor-Zanik now features 3 styles of mineralization with 7 metals; the Brezani gold bearing system sits 12 km southeast of the high-grade, polymetallic Cumavici discovery (see Figure 1) which intercepted:
- 2 g/t AgEq. over 4.0 m including 1634.4 g/t AgEq. over 2.0 m
- 1 g/t AgEq. over 2.0 m
- 5 g/t AgEq. over 8.7 m including 1196.6 g/t AgEq. over 2.0 m (see Company news releases from September 8th and October 22nd, 2022);
- Open at depth with favorable lithologies: BREDD002 terminated in elevated gold mineralization at 215 m depth; the Company interprets the elevated gold at the end of the drillhole to be associated with another mineralized zone and silica-chlorite-sericite altered intrusive lithologies downhole highlight the potential for porphyry style mineralization which will require further drill testing (see Figure 3);
- Exploration upside: gold-bearing target at Brezani coincides with a resistive volume of rock above a large conductivity anomaly (> 600 m wide, > 60 mS/m) interpreted to represent porphyry style mineralization (see Figure 3), which remains untested.
Terra Balcanica President and CEO, Dr. Aleksandar (Alex) Miskovic, commented: “We are extremely excited about the Brezani gold discovery located over 12 km southeast of the high-grade, polymetallic discovery made by Terra Balcanica at the Cumavici target last year. The Viogor-Zanik project is clearly underexplored as we have identified a number of quality exploration targets through our detailed targeting in 2021 and we have now confirmed three different styles of magmatic-hydrothermal mineralization. The intercepted metasomatized hornfels suggests that we are in the upper part of a large retrograde skarn-porphyry system at Brezani with the gold mineralization encountered from surface and a significant potential for either a deeper porphyry or a sulphide rich Cu-Au proximal skarn mineralization. The spatial coincidence of precious metals with a plus 1.2 km wide magnetic anomaly and the presence of a strong electric conductor at 400 m depth detected via airborne geophysics gives us confidence that we have a large potential mineralized system on our hands. We look forward to more assays from the 2022 program which will be released over the coming weeks.”
|Drillhole||From (m)||To (m)||Length (m)||Au (g/t)||Ag (g/t)||Cu (%)||Zn (%)||AuEq (g/t)|
Table 1. Assay results of key mineralized intervals for diamond drillholes BREDD001 and BREDD002. Interval lengths reported are drilled lengths and not true widths. AuEq calculation assumes metal prices of US$1,900/oz for gold (Au), US$24.00/oz for silver (Ag), US$4.00/lb for copper (Cu) and US$1.65/lb for zinc (Zn). Metallurgical recoveries of 95% have been adopted based on metallurgical testwork by Dundee Precious Metals Inc. (TSX:DPM) on their Coka Rakita Au skarn in Serbia (see Note 1 below). BREDD001 was terminated early at 28.6 meters due to increased levels of core loss.
Figure 1. Terra Balcanica’s 216 km2 Viogor-Zanik project in eastern Bosnia and Herzegovina with the key drill target areas and their associated styles of mineralization: (i) the epithermal Cumavici corridor, (ii) the Olovine porphyry target and (iii) the southwesterly Brezani skarn/porphyry system is located approximately 12 km SE of the Cumavici Ridge discovery drillholes. (Click here to view image)
Brezani is located 8.4 km south of the Mineco Ltd.Sase Mine which produces approximately 330 kt of lead-zinc-silver-gold concentrate per year (Figure 1). Brezani hosts components of a large magmatic-hydrothermal system discovered by geophysical and geochemical surveys (Figure 2).
Drillhole BREDD001 was terminated at 28.6 m depth due increased levels of core loss. The core returned 28.6 m at 0.58 g/t AuEq from surface. The lithologies intercepted were strongly oxidized diorites and hydrothermal breccias, ending in a calc-silicate hornfels. Au contents of up to 1.9 m at 2.46 g/t Au are observed in hydrothermal breccias of dioritic intrusive rocks, apopheses of an underlying pre/inter-mineral intrusion.
Figure 2. Geological map highlighting the 1.2km wide, 95th percentile magnetic anomaly at the Brezani target. The strongest magnetic response remains untested at depth, however correlates to Au in surface trenches, quartz vein bearing sericitized diorites and calc-silicate altered hornfels with elevated concentrations of proximal pathfinder elements (Bi-Te) from soil geochemistry. Distal zonation sees strong argillic alteration and a Zn-Mn geochemical halo. (Click here to view image)
Drillhole BREDD002 was designed as a subsequent hole to BREDD001 to test the resistive hanging wall existing below the exposed calc-silicate hornfels. The drillhole collar was centered on an 850 m wide Au in soil anomaly and located 65 m NW from the previously completed exploratory trenches that yielded 32 m at 0.54 g/t AuEq (See Company’s news release dated August 17th, 2022). The mineralized interval reporting 88.0 m at 0.61 g/t AuEq from surface includes 7 m of dilution from a late, post-mineralization diorite dyke.
Figure 3. Conductivity profile of the Brezani target with >95th percentile magnetic anomaly. BREDD002 tests the resistive volume above an abrupt change into coincident high magnetic and elevated electrical conductivity response below 300 m depth which culminates at >60 mS/m at 450 m of depth. Dashed line represents distance from the end of BREDD002 to the top of conductor. (Click here to view image)
The sulphides encountered at Brezani are characterised by both disseminated and intervals of semi-massive sphalerite-chalcopyrite (Figure 4). Pyrrhotite is the dominant iron sulphide, with pyrite uncommon. The gold is controlled by lithology and associated with skarns, calc-silicate hornfels and specific intrusive phases. Quartz veins host pyrrhotite, sphalerite, chalcopyrite and molybdenite. A less reactive hornfels is present between 87.2 and 199 m depth but silicified diorite reappears between 214 and 215 m depth where the drillhole ended in Au mineralization returning 0.26 g/t Au.
Intermediate sulphidation veins were observed at 156 m and 168 m downhole returning 1.0 m at 0.39 g/t Au and 1.0 m at 0.34 g/t Au, 12.1 g/t Ag, respectively. The presence of these veins confirms another mineralization style within the broad porphyry (Cu) model. Mineralogy is varied with pyrrhotite, pyrite, sphalerite, galena, arsenopyrite and bismuthinite present within fault hosted, quartz-carbonate veins (Figure 5).
Figure 4. Retrograde skarn with sphalerite-chalcopyrite at 37.5 m (2.74 g/t Au). (Click here to view image)
Figure 5. Intermediate sulphidation veins in silicified hornfels of BREDD002. (Click here to view image)
|Hole ID||Easting||Northing||Elevation||Dip||Azimuth||Depth (m)||Recovery (%)|
Table 2. Collar location and core recoveries for diamond drillhole BREDD001 and BREDD002 (UTM; WGS84). BREDD001 drillhole experienced a cumulative core loss of 2.0 m between 14.9-15.4 m, 16.3-16.9 m, 19.6-20.1 m, and 25.8-26.2 m, while BREDD002 experienced core loss of 0.8 m between 24.0-24.8m.
The Brezani target bears lithological similarities with the Rogozna Project operated by Zlatna Reka Resources located 150 km SW within the Oligo-Miocene Tethyan belt in neighbouring Serbia. The Rogozna Au-Cu skarn deposit has a 2021 JORC compliant inferred mineral resource of 64 Mt grading 0.7 g/t Au and 0.2% Cu (2.15 Moz Au total), calculated using multiple indicator kriging on 154 drillholes, totalling 90,278 drill metres (https://ibaera.com/rogozna-2-15moz-au-eq-maiden-resource-estimate/).
Further Drilling: The coincident strong magnetic and conductivity anomalies (> 60 mS/m) below the resistive surface shell at Brezani remains untested and presents a promising target for increased, interconnected sulphide content characteristic of mineralized porphyry shells (Figure 3), which will be the Company’s priority during the 2023 drilling campaign. Follow up will be undertaken from other locations within the Au-in-soil anomaly to assess lithological variability and grade of the Au skarn along strike. Additional drilling will test Au anomalous rock chips within argillically altered volcanics and hydrothermal breccias thus offering a chance for testing multiple styles of mineralization within a broad porphyry model.
Note 1: https://www.dundeeprecious.com/English/Corporate-News/press-release-details/2023/Dundee-Precious-Metals-Announces-Discovery-of-Significant-High-Grade-Deposit-at-oka-Rakita-Results-Include-Drill-Intercept-of-40-metres-at-63.6-gt-Au-and-0.11-Cu/default.aspx
Half core (PQ3 and HQ3) samples were delivered to ALS Bor, Serbia for sample preparation and subsequent wet chemical analysis at the Loughrea laboratory in Ireland, an ISO/IEC 17025:2017 certified test facility. Sample preparation PREP-31BY method involved crushing the core to 70% less than 2 mm, rotary split 1.0 kg and pulverizing the split to greater than 85% passing 75 microns. Silver and base metals were analysed by ICP MS after a four-acid digest (ME-MS61). Gold was assayed by 30g fire assay with ICP AES finish (Au-ICP21). Over limit samples for base metals were re-analysed by the four-acid digest ICP-AES analyses termed ME-OG62. Control samples comprising the certified reference material CDN-ME-1501 (Canadian Resource Labs Ltd.), quarter core field duplicates and blanks were inserted at a rate of 5% and investigated as part of the Company’s quality assurance and quality control program.
Dr. Aleksandar Mišković, P.Geo, is the Company’s designated Qualified Person for this news release within the meaning of National Instrument 43-101 Standards of Disclosure of Mineral Projects (“NI 43-101”). Dr. Mišković has reviewed and validated the information contained in this news release as factual and accurate.
Terra Balcanica is a polymetallic exploration company targeting large-scale mineral systems in the Balkans of southeastern Europe. The Company has 90% interest in the Viogor-Zanik Project in eastern Bosnia and Herzegovina, 100% of the Kaludra and Ceovishte mineral exploration licences in Serbia. The Company emphasizes responsible engagement with local communities and stakeholders. It is committed to proactively implementing Good International Industry Practice (GIIP) and sustainable health, safety and environmental management.