Mexico Mining Industry - Sonoro Files Nl 43-101 Technical Report for the Cerro Caliche Project in Mexico -- 26/7/2019.
The independent Technical Report titled "NI 43-101 Technical Report on the Cerro Caliche Gold Project, Cucurpe Mining District of Sonora State, Northwestern Mexico", dated July, 26, 2019 (the "Technical Report") was prepared by independent Qualified Persons, Derrick Strickland, P.Geo., and Robert Sim, P.Geo., Sim Geological Inc.
Estimate of Mineral Resources for the Cerro Caliche Project
Average Grade Contained Metal Category Tonnes AuEq Au Ag AuEq Au Ag (000) (g/t) (g/t) (g/t) (koz) (koz) (koz) Inferred 11,470 0.545 0.495 4.3 201 183 1,601
Note: The estimates in the above table are limited inside the $1,500/oz Au pit shell. The base case cut-off grade is 0.25 g/t gold equivalent (AuEq), where AuEq = Au g/t + (Ag g/t x 0.01133). Mineral resources are not mineral reserves because the economic viability has not been demonstrated. There are no mineral reserve estimates for the Cerro Caliche project. It is reasonably expected that a majority of Inferred mineral resources could be upgraded to Indicated (or Measured) mineral resources with continued exploration.
Kenneth MacLeod, President and CEO of Sonoro commented, "The establishment of a maiden estimate of mineral resources at Cerro Caliche provides a strong foundation from which potentially to expand the mineralization along strike and at depth from many of the mineralized zones documented in the Technical Report. We are pleased to confirm that many of the recommendations contained in the Technical Report are either being actively pursued, or will be implemented shortly, including; metallurgical testing, 3D modelling of the structure, and a 7,000 meter drilling program comprising diamond drilling and reverse-circulation drilling to increase the confidence of the known mineralization and to identify potential expansion of known mineralization."
The estimate of mineral resources is based on a total of 21,091 meters of reverse circulation drilling in 200 holes. Of these, 10,328 meters in 96 holes were drilled by Sonoro, plus 7,725 meters in 86 holes were drilled by Corex Gold and 3,038 meters in 18 holes were drilled by Paget Southern, both previous operators of the Cerro Caliche project. The reported mineral resources were estimated using a three-dimensional block model with a nominal block size of 6 x 6 x 5 meters (LxWxH). Drill holes, collared from surface, penetrate the steeply dipping mineralized zones to depths of generally within 125 meters below surface but several holes have intersected gold mineralization to depths approaching 200 meters below surface.
The resource estimate was generated using drill hole sample assay results and the interpretation of a geological model which relates to the spatial distribution of gold and silver. Interpolation characteristics are defined based on the geology, drill hole spacing, and geostatistical analysis of the data. The effects of potentially anomalous high-grade sample data, composited to 1.5-meter intervals, are controlled using both traditional top-cutting as well as limiting the distance of influence during block grade interpolation.
Block grades are estimated using ordinary kriging and have been validated using a combination of visual and statistical methods. Mineral resources in the Inferred category extend for a maximum distance of 100 meters from a drill hole.
The estimate of mineral resources is constrained within a pit shell to establish reasonable prospects for eventual economic extraction. The pit shell was generated using the following projected technical and economic parameters:
* Mining (open pit) US$1.75/t * Processing US$6.80/t * G&A US$1.50/t * Gold price US$1,500/oz * Silver price US$17.00/oz * Gold process recovery 72% * Silver process recovery 30% * SG 2.50 * Pit slope 50 degrees * Gold Equivalent calculation AuEq = Au g/t + (Ag g/t x 0.1133) * Base case Cut-off grade 0.25 g/tAuEq
The Cerro Caliche deposit exhibits features that are typical of low-sulphidation epithermal style deposits. Mineralized zones are often structurally controlled and extend for strike lengths of up to 1 km and to depths approaching 200 m below surface.
Many of the mineralized zones remain "open" along strike and at depth. Numerous other mineralized zones have been identified by surface mapping and surface geochemical rock sampling.
The majority of the rocks that host the mineral resources at Cero Caliche are highly oxidized and it is likely that the deposit is amenable to low-cost heap leach extraction methods. There are several proximal deposits that have similar geologic characteristics that are currently extracting gold and silver through heap leach extraction.
Based on the evaluation of the data available from the Cerro Caliche Project, the authors of the Technical Report have drawn the following conclusions:
* The Cerro Caliche deposit exhibits features that are typical of low-sulphidation epithermal style deposits. Mineralized zones are often structurally controlled and extend for strike lengths of up to 1 km and to depths approaching 200 m below surface.
* Many of the mineralized zones remain "open" along strike and at depth. Numerous other mineralized zones have been identified by surface mapping and surface geochemical rock sampling.
* Exploration activities conducted by Sonoro and the previous operators of the property followed industry standards, and the resulting database is considered to be reliable to support estimates of mineral resources.
* Drilling to date has outlined an estimated Inferred mineral resource of 11.5M tonnes at an average grade of 0.495 g/t gold and 4.3 g/t silver. It is assumed that the mineral resource is potentially amenable to open pit extraction methods.
* Preliminary metallurgical test work has only recently been initiated by Sonoro. The majority of the rocks that host the mineral resources at Cerro Caliche are highly oxidized and it is likely that the deposit is amenable to low-cost heap leach extraction methods. There are several proximal deposits that have similar geologic characteristics that are currently extracting gold and silver through heap leach extraction.
* The authors of the Technical Report are not aware of any known factors related to metallurgical, environmental, permitting, legal, title, taxation, socio-economic, marketing or political issues which could materially affect the mineral resource estimates.
Based on the review of the data provided, the authors recommend the following next steps to advance the Cerro Caliche project:
* Conduct a drilling program that includes:
# A 500 m infill drilling program comprising large diameter (PQ) core to provide valuable structural and mineralization information.
# A 6,500 m reverse-circulation drilling program to increase the confidence of the known mineral resource and identify potential expansion of known mineralization.
* Conduct a detailed metallurgical analysis of the known mineralized area.
* Review the existing data to integrate the geology, alteration, observations, and known structure into a 3D model. This will help target areas for potential expansion.
* Continue to explore for extensions of existing mineralized zones.
* Drill a series of diamond drill holes in each mineralized zone to gain additional information related to geologic and metallurgical characteristics.
* Conduct a suite of cyanide soluble gold assays on a select suite of samples to better understand the nature and distribution of soluble gold.
* Attempt to locate the older drilling data generated by Cambior.
The 1,350-hectare Cerro Caliche concessions are located 45 kilometers east southeast of Magdalena de Kino in the Cucurpe-Sonora Mega-district of Sonora, Mexico. Multiple historic underground mines were developed in the concession including Cabeza Blanca, Los Cuervos, Japoneses, Las Abejas, Boluditos, El Colorado, Veta de Oro and Espanola. Mineralization types of the Cucurpe-Sonora Mega-district include variants of epithermal low sulfidation veins and related mineralized dikes and associated volcanic domes. Local altered felsic dikes cut the mineralized meta-sedimentary rock units and may be associated with mineralization both in the dikes and meta-sedimentary rocks.
Host rocks include Jurassic-Cretaceous meta-sedimentary rock units including argillite, shale, quartzite, limestone, quartz pebble conglomerate and andesite. Younger intrusive rock consisting of medium coarse-grained granodiorite-granite is present in the westerly parts of the concessions near the historic Cabeza Blanca mine. It is apparent that veining cuts and pervasively alters the intrusive stock. Rhyolite occurs in irregular bodies distributed in higher elevations in the northerly part of the concession, including the Rincon area, where it occurs as flows, sills, dikes and rhyolite domes. Part of the rhyolite is mineralized and appears to be related to epithermal gold mineralization throughout the property.
Robert Sim, P.Geo., a Qualified Person as defined by NI 43-101, is responsible for the estimate of mineral resources presented in this news release and has reviewed, verified and approved the contents of this news release as they relate to the mineral resource estimate.
Stephen Kenwood, P. Geo., a director of Sonoro, is a Qualified Person within the context of National Instrument 43-101 and has read and approved this news release.
About Sonoro Metals Corp.
Sonoro Metals Corp. is a publicly listed exploration and development company with two exploration stage precious metal properties in Sonora State, Mexico. The company has highly experienced operational and management teams with proven track records for the discovery and development of natural resource deposits.
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|Date:||Aug 14, 2019|
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