Velocity Files Updated Technical Report at Obichnik Gold Project, Southeast Bulgaria


VANCOUVER, British Columbia, Dec. 08, 2021 (GLOBE NEWSWIRE) — Velocity Minerals Ltd. (TSXV: VLC) (“Velocity” or the “Company”) reports that it has filed an updated National Instrument 43-101 Standards of Disclosure for Mineral Projects (“NI 43-101”) technical report for the Durusu deposit at the Obichnik gold project (“Obichnik” or the “Project”), southeast Bulgaria (the “Updated Technical Report”). The Updated Technical Report incorporates an updated Inferred Mineral Resource estimate for the Project, and incorporates the results of recently completed metallurgical test-work, which indicates leach recoveries of approximately 95% for combined oxide and transitional material, and 96% for fresh / sulphide material.

The Updated Technical Report entitled “NI 43-101 Technical Report Exploration and Mineral Resource Estimation for the Obichnik Property, Republic of Bulgaria” is dated December 8, 2021 and has an effective date of December 6, 2021, and was prepared by Jonathon Abbott, BASc, MAIG. The Updated Technical Report is available on the Company’s SEDAR profile at www.sedar.com and on the Company’s website at www.velocityminerals.com.

The Updated Technical Report updates and replaces the previous technical report for the Project dated March 20, 2021 (the “March 2021 Report”).

Resource Estimate Methodology and Assumptions

Recoverable resources were estimated for the Durusu Zone at Obichnik using Multiple Indicator Kriging (“MIK”) with block support adjustment, a method that has been demonstrated to provide reliable estimates of recoverable open pit resources in gold deposits of diverse geological styles. The resource estimates include a variance adjustment to give estimates of recoverable resources above gold cut off grades for selective mining unit (“SMU”) dimensions of 5m east by 2m north by 2m in elevation. The variance adjustments were applied using the direct log-normal method.

The estimates are based on data from diamond drilling undertaken by Velocity since 2019 and includes drilling information available on the 10th of February 2021 comprising 37 holes for 6,820m. Velocity’s diamond holes are inclined to the southwest at generally 50o at generally around 25m spacing along generally 50 m spaced traverses with rare closer spaced holes.

Resource modelling incorporated two steeply northwest dipping mineralized domains interpreted from 2m down-hole composited gold grades and capturing intervals of greater than 0.1 g/t (Figure 1, Figure 2). The main, northern domain extends over approximately 380m of strike with an average width of around 80m. The subsidiary southern domain averages around 40m wide over 320m of strike. Mineralization is characterized as structurally controlled steep epithermal replacement of the volcanic host with a large envelope of alteration that forms part of a 2.5km by 1km wide intrusive related hydrothermal mineralizing system.

Model blocks are categorized by oxidation zone from triangulated surfaces representing the base of complete oxidation and top of fresh rock interpreted from geological logging of Velocity’s diamond holes. Within the resource area the depth to the base of complete oxidation averages around 55m, with fresh rock occurring at an average depth of around 68m.

Bulk densities of 2.30, 2.50 and 2.55 tonnes per cubic metre were assigned to completely oxidized, transitional and fresh material respectively on the basis of 30 immersion density measurements performed by Velocity on diamond drill core samples.

All class grades were for MIK modelling determined from bin mean grades with the exception of the upper bins, which were reviewed on a case by case basis for each mineralized domain/oxidation zone subset and bin grades selected on the basis of bin mean, or median with or without exclusion of high grade composites. This approach was adopted to reduce the impact of a small number of outlier composites.

Table 1 show the Inferred Mineral Resource estimates for Durusu and Table 2 shows the estimates by oxidation zone. The figures in these tables are rounded to reflect the precision of the estimates and include rounding errors.

The Updated Technical Report reports Mineral Resources within an optimized pit shell generated with the parameters shown in Table 3. These parameters were derived from recent metallurgical test-work performed on samples of Durusu mineralization as described below and the parameters used for generating the pit shell constraining Mineral Resource estimates for Velocity’s Rozino deposit, for which evaluation is more advanced than Durusu. The gold price of $US 1,500/oz was selected from the trailing five-year average gold price with appropriate rounding. These parameters generate a gold cut-off grade of 0.3 g/t for oxide, transitional and fresh mineralization and this cut-off was selected for Mineral Resource reporting.  

Table 1: Durusu Inferred Mineral Resource estimates

Effective date of estimates: 6th December 2021
Cut off grade 0.3 g/t Au
Tonnes (Mt) Grade (Au g/t) Metal (Au koz)
3.2 1.2 123

Table 2: Mineral Resource estimates by oxidation zone

Effective date of estimates: 6th December 2021
Cut off grade 0.3 g/t Au
Zone Tonnes (Mt) Grade (Au g/t) Metal (Au koz)
Oxide 1.7 1.3 71
Transition 0.4 1.3 17
Fresh 1.1 0.9 32
Total 3.2 1.2 123
Table 3: Parameters Used to Generate Pit Shell to Constrain Mineral Resource Estimates
Gold price $US 1,500 per troy ounce
Cost per tonne of material mined $US 2.60 per tonne
Cost per tonne of material milled $US 11.75 per tonne
Metallurgical recovery Oxide and Transition 94.65%, Fresh 95.94%
Refining charge $US 1.44 per troy ounce
Wall angle 45o

The Updated Technical Report differs from the March 2021 Technical Report in that the Mineral Resources are reported from the February 2021 block model constrained within an optimal pit shell rather than being truncated at 180 m depth.

Figure 1. Plan view of Inferred Mineral Resource extents relative to drill hole dataset
https://www.globenewswire.com/NewsRoom/AttachmentNg/e51b472a-c266-4ab6-b505-1607d5b3af37

Figure 2. Representative section of Mineral Resource Estimate scaled
and coloured by proportion above 0.3 g/t gold cut off grade
https://www.globenewswire.com/NewsRoom/AttachmentNg/2024965c-7c71-4d11-a26d-d67a684466ec

Metallurgical Testing

In August 2021 two composite samples of jaw-crushed coarse reject samples of Velocity diamond core were submitted to Eurotest Control EAD in Sofia (“Eurotest”) for metallurgical test-work. These samples were selected as representing combined oxidised and transitional and fresh mineralization respectively as follows.

  • Combined oxide and transition sample: ОМ-ОТ-01 was produced from 481 sample intervals comprising 391 and 90 samples from intervals geologically logged as oxidised and transition respectively.
  • Fresh sample: ОМ-F-02 was produced from 343 sample intervals geologically logged as fresh.

The combination of oxidised and transitional material into a single sample for metallurgical test-work reflects the small proportion of Mineral Resources hosted by transitional material and the expected metallurgical similarity of the two material types.

Eurotest, Sofia, unified and homogenized each of the samples by hand-mixing for 30 minutes, followed by passing twice each through a riffle splitter and rotary splitter, with final splitting of homogenized sample into 1 Kg portions. The samples were subjected to test-work comprising complete chemical and mineralogical characterization, phase analysis (Diagnostic Leach Test) of gold present in each sample and testing to determine cyanide leaching kinetics and degree of gold recovery.

Gold head grades were determined for each sample from the average of four fire assays. The test results, including agitated cyanide leaching under the conditions shown in Table 4 demonstrate that mineralization represented by the two composite samples is amenable to standard Carbon in Leach (CIL) processing, with estimated gold recoveries of around 95% and 96% for the oxide/transition and fresh samples respectively. The test-work does not indicate any processing factors or deleterious elements that could have a significant effect on potential economic extraction.

Metallurgical test work for Obichnik mineralization available in March 2021 and described in the March 2021 Report comprised preliminary metallurgical tests performed by Geoengineering summarised in a 2010 Commercial Discovery report. Details of this older test-work, which gave gold recoveries of 80.6% to 97.6% from floatation tests and 81.3% from cyanide leach tests respectively are unknown. The Updated Technical Report describes the 2021 Eurotest metallurgical test work and summarises the older test-work. The author of the Updated Technical Report regards the 2021 Eurotest analyses as a more reliable indication of potential metallurgical recoveries for processing of Durusu mineralization than the older results.  

General Notes…



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