(TheNewswire)
Outlines ProcessFlow to Further Optimize Rapid Recovery Potential
Highlights
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Recovery Results for Heap LeachingMatch Regional Operating Mines; Head Grade ExceedsExpectations
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62% Recovery of Gold Achieved Over46-day Leaching Period
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Report Confirms with Increase inIrrigation Flowrate, Higher Recovery Can Be Achieved
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Head Grade Calculated at 1.9 g/t Auand 7 g/t Ag; Extracted Grade Calculated at 1.2 g/t Au and 3 g/tAg
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Bulk Sample Only Included CoarseFraction of Material (+3/4” to +1/8”)
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Fine Fraction (-1/8”) IndicatesRapid Recovery with Agitated Leach
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Recap of Fine Fraction and GravityRecovery Results
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Agitated Bottle Roll Test ReturnedRapid and High Recovery Results:
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80% Recovery of Gold and 94% Recoveryof Silver after Rapid 24-hourRetention Time
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Gravity Recovery with Agitated LeachResults of Five Composite Samples Returned
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95 to 99% Recovery of Gold
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73 to 97% Recovery of Silver
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Includes the Recovery of 99% Au and73% Ag from Drill Core Composite at 120-meter Depth
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Video Summary:
Calgary, Alberta - TheNewswire - August 22, 2023 - Tocvan Ventures Corp. (the “ Company ” ) (CSE:TOC ) ( OTC:TCVNF ) ( FSE:TV3) , is pleased to provide results from aBulk Sample completed at its Pilar gold-silver project Sonora, Mexico.Independent Qualified Professionals at LTM of Hermosillo have provideda final report after the completion of final analytical results. Thereport findings include a baseof 62% recovery of gold and 47% recovery ofsilver. Head grade results were calculated by LTM as 1.9 g/t Au and 7 g/t Ag , with calculated recoverable metal extracted at 1.2 g/t Auand 3 g/t Ag. Importantly the report notes that the first 30 days ofleaching was restricted by an erratic and low flowrate of cyanideleaching solution. This was corrected once identified through theinstallation of updated irrigation systems and began instantlyimproving irrigation flowrate and metal recovery. LTM notes thatincreased gold and silver recovery is likely with a more consistentflowrate. LTM has recommended a duplicate column leach study ofavailable bulk sample composite material to verify the ultimate goldand silver extractions under heap leach. It is also important to notethe low cyanide (NaCN) consumption recorded (0.19 kg/t), indicatinglow cost of operation. In addition to the heap leach study, anagitated bottle roll test was completed by LTM on a bulk samplecomposite for comparison of the two methods. Rapid gold and silverrecovery was recorded from minus 20 Mesh material returning 80% recovery of gold and 94%recovery of silver after just 24-hours of retention time . Follow-on agitated leach and gravity tests are recommendedto further evaluate the ability to utilize rapid recovery methods inlieu of the slower heap leach method. The Company is extremely pleasedwith the analytical results and insights gained through the bulksample process which will guide future development and provide addedconfidence in the optimal extraction method.
“The Bulk Sampleprocess has been extremely important to the understanding of thesurface expression of mineralization at Pilar along with defining apath towards optimal gold and silver recovery.” Stated Brodie Sutherland, CEO. “We areencouraged by the strong heap leach results for gold where the datasuggests recovery can be improved through increased leaching solutionflowrate over a consistent and longer leaching period. Perhaps themost encouraging development from the study is the characterization ofexposed gold and silver amenable to rapid gravity and agitated leachrecovery. A quicker turnaround for metal extraction at very highrecovery rates adds a new positive factor to the development path ofthe relatively high-grade nature of Pilar. Having optionality toexplore both methods as viable extraction techniques makes Pilar aunique and standout deposit for the region and with the potential nowto explore an even greater area around to add to the potentialresource size makes us even more excited for the future of theproject.”
Figure 1. HeapLeach Bulk Composite Sample. Flowrate versus time and Cumulative Goldand Silver Extraction versus time. Irrigation flowrate was improvedafter day 30 of the test having a positive impact on metalrecovery.
LTM Conclusions and Recommendations
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A cyanide agitated bottle roll testconducted on the Bulk Composite Sample at a grind size of 100% minus20 Mesh (850 microns) showed high gold and silver extractions ofapproximately 81% and 99% respectively after a retention time of 72hours. It is important to point out that fast gold and silverdissolution kinetics were obtained and gold and silver extractions of80% and 94% respectively were achieved after 24 hours of retentiontime.
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It is recommended to conduct acyanide agitated bottle roll study on the Bulk Composite Sample atthree grind sizes of P 80 of 100 Mesh (150 µm),140 Mesh (106 µm) and 200 Mesh (75 µm) to evaluate the impact ofgrind size upon gold and silver extraction.
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The cyanide pilot heap testconducted on the Bulk Composite Sample at a crush sizes of+3/4”+1/8” showed gold and silver extractions of 61.84% and 47.27%respectively after a leach cycle of 46 days. Problems in the solutionpumping system during the first 30 days of leach cycle affected thegold and silver extractions during the first 30 days of leach cycle.Therefore, it is recommended to conduct a duplicate column tests onthe Bulk Composite Sample at a crush sizes of +3/4”+1/8” fordetermining the ultimate gold and silver extractions under heap leachtype of leaching regime.
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It is recommended to conductadditional metallurgical test work on the Bulk Composite Sample at acrush size of 100% -1/8” which will provide additional informationon the overall gold and silver recoveries and potential processoptions for processing the mineral resources from the El Pilar GoldProject. The following paragraphs summarize the recommended testworkand the objectives:
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A) Two cyanidelocked cycle column tests (1 Test with Agglomeration with PortlandCement 1 Test Without Agglomeration) to evaluate if it is feasible toleach the fine fraction (100% -1/8”) of the Bulk Composite Samplewithout presenting percolation problems.
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B) GravityConcentration at a grind of 80% minus 150 µm using a KnelsonLaboratory Concentrator. The objective of the test will be to evaluatethe amenability of recovery the free gold contained in the finefraction of the Bulk Composite Sample.
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C) GravityConcentration at a grind of 80% minus 150 µm using a WilfleyConcentrator Table. The objective will be to evaluate the amenabilityof recovery potential free gold contained in the fine fraction of theBulk Composite Sample using the Wilfley Concentrator Table.
Figure2. Cyanide Agitated BottleRoll Test from Bulk Composite Sample. Rapid recovery of gold (80%) andsilver (94%) achieved after 24-hours of retention time.
Diagnostic LeachStudy Summary
Full results from the Diagnostic Leach Study areavailable on the Company’s website and in the March 29 th news release.A summary is provided below to further demonstrate the potential toutilize rapid recovery methods.
Table1. Summary of Results fromthe Precious Metals Diagnostic Leach Study completed by LTM.
Sample ID | Location | Head Screen Assay | Gravity Concentrate Assay | Total Recoverable by Gravity andAgitated Cyanide Leach | |||
Au (g/t) | Ag (g/t) | Au (g/t) | Ag (g/t) | Au (%) | Ag (%) | ||
494741 | Main Zone (Surface) | 6.2 | 23 | 76.2 | 237 | 95 | 78 |
494743 | Main Zone (Surface) | 8.2 | 68 | 117.0 | 1152 | 98 | 97 |
494745 | Main Zone (Surface) | 2.7 | 9 | 35.6 | 82 | 97 | 90 |
494747 | 4-T (Surface) | 20.4 | 74 | 290.3 | 568 | 98 | 85 |
494749 | Main Zone (Drill Core) | 24.9 | 9 | 231.1 | 53 | 99 | 73 |
Share Issuance
The Company plans to issue 300,000 Common Shares at adeemed price of $0.50, as a debt settlement to a consultant of theCompany. The Company currently has 40,285,107 Common Sharesoutstanding.
About the Pilar Property
The Pilar Gold-Silver property has recently returnedsome of the regions best drill results. Coupled with encouraging goldand silver recovery results from metallurgical test work, Pilar isprimed to be a potential near-term producer. Pilar is interpreted as astructurally controlled low-sulphidation epithermal system hosted inandesite rocks. Three primary zones of mineralization have beenidentified in the north-west part of the property from historicsurface work and drilling and are referred to as the Main Zone, NorthHill and 4-T. The Main Zone and 4-T trends are open to the southeastand new parallel zones have been recently discovered. Structuralfeatures and zones of mineralization within the structures follow anoverall NW-SE trend of mineralization. Mineralization extends along a1.2-km trend, only half of that trend has been drill tested so far. Todate, over 23,000 m of drilling has been completed.
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2022 Phase III Diamond DrillingHighlights include ( all lengths are drilled thicknesses ):
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116.9m @ 1.2 g/t Au, including 10.2m@ 12 g/t Au and 23 g/t Ag
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108.9m @ 0.8 g/t Au, including 9.4m @7.6 g/t Au and 5 g/t Ag
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63.4m @ 0.6 g/t Au and 11 g/t Ag,including 29.9m @ 0.9 g/t Au and 18 g/t Ag
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2021 Phase II RC Drilling Highlightsinclude ( all lengths are drilled thicknesses ):
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2020 Phase I RC Drilling Highlights include ( all lengths are drilledthicknesses
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94.6m @ 1.6 g/t Au, including 9.2m @10.8 g/t Au and 38 g/t Ag;
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41.2m @ 1.1 g/t Au, including 3.1m @6.0 g/t Au and 12 g/t Ag ;
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24.4m @ 2.5 g/t Au and 73 g/t Ag,including 1.5m @ 33.4 g/t Au and 1,090 g/t Ag
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15,000m of Historic Core RCdrilling. Highlights include:
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61.0m @ 0.8 g/t Au
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16.5m @ 53.5 g/t Au and 53 g/t Ag
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13.0m @ 9.6 g/t Au
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9.0m @ 10.2 g/t Au and 46 g/t Ag
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About Tocvan VenturesCorp .
Tocvan is a well-structured exploration developmentcompany. Tocvan was created in order to take advantage of theprolonged downturn in the junior mining exploration sector, byidentifying and negotiating interest in opportunities where managementfeels they can build upon previous success. Tocvan has approximately40 million shares outstanding and is earning 100% into two excitingopportunities in Sonora, Mexico: the Pilar Gold-Silver project and theEl Picacho Gold-Silver project. Management feels both projectsrepresent tremendous opportunity to create shareholder value.
Brodie A. Sutherland, P.Geo., CEO for Tocvan VenturesCorp. and a qualified person (" QP ") as definedby Canadian National Instrument 43-101, has reviewed and approved thetechnical information contained in this release.
Quality Assurance / QualityControl
Oversight and management of the Bulk Sample wascompleted by an independent group of qualified professionals at LTM(Laboratorio Tecnológico de Metalurgia) of Hermosillo. As part of theCompany’s robust QA/QC procedures, duplicate samples of cyanidesolutions are submitted to LTM in Hermosillo, Sonora. LTM facilitiesare an ISO 17025 and ISO 9001:2015 certified lab. A second duplicateof cyanide solutions are submitted to SGS in Durango. Gold and silverare analyzed using 30g nominal weight fire assay with AA finish for Auand gravimetric determination for Ag. Other elements are analyzedusing aqua regia digestion with an ICP finish.
Cautionary Statement RegardingForward Looking Statements
This news release contains“forward-looking information” which may include, but is notlimited to, statements with respect to the activities, events ordevelopments that the Company expects or anticipates will or may occurin the future. Forward-looking information in this news releaseincludes statements regarding the use of proceeds from the Offering.Such forward-looking information is often, but not always, identifiedby the use of words and phrases such as “plans”, “expects”,“is expected”, “budget”, “scheduled”, “estimates”,“forecasts”, “intends”, “anticipates”, or “believes”or variations (including negative variations) of such words andphrases, or state that certain actions, events or results “may”,“could”, “would”, “might” or “will” be taken, occur orbe achieved.
These forward-looking statements,and any assumptions upon which they are based, are made in good faithand reflect our current judgment regarding the direction of ourbusiness. Management believes that these assumptions are reasonable.Forward-looking information involves known and unknown risks,uncertainties and other factors which may cause the actual results,performance or achievements of the Company to be materially differentfrom any future results, performance or achievements expressed orimplied by the forward-looking information. Such factors include,among others, risks related to the speculative nature of theCompany’s business, the Company’s formative stage of development and the Company’s financialposition. Forward-looking statements contained herein are made as ofthe date of this news release and the Company disclaims any obligationto update any forward-looking statements, whether as a result of newinformation, future events or results, except as may be required byapplicable securities laws.
There can be no assurance thatforward-looking information will prove to be accurate, as actualresults and future events could differ materially from thoseanticipated in such statements. Accordingly, readers should not placeundue reliance on forward-looking information.
For more information, please contact:
TOCVAN VENTURES CORP.
Brodie A. Sutherland, CEO
820-1130 West Pender St.
Vancouver, BC V6E 4A4
Telephone: 1 888 772 2452
Email: ir @tocvan.c a
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