In January 2018, Sonoro Metals, through its wholly-owned Mexican subsidiary, Minera Mar De Plata, SA de C.V., entered into the first of five option agreements to acquire a 100% interest in the Cerro Caliche Group of Concessions located in the municipality of Cucurpe, in northern Sonora State, Mexico. Home to multiple historic mining sites, including Cabeza Blanca, Los Cuervos, Japoneses, Las Abejas, Boluditos, El Colorado, Veta de Oro and Espanola, the property has also been the subject of drill programs by Cambior Gold, Corex Gold Corp. and Paget Sothern Resources. Historical data, combined with results from Sonoro’s current exploration activities, confirm the existence of a broadly mineralized low-sulphidation, epithermal vein system with continuing potential to develop a large tonnage resource suitable for open pit mining.
The Cerro Caliche gold project is strategically situated between two world-class mining districts of the Sierra Madre Gold Belt and the Sonoro-Mojave Megashear. Located approximately 45 kilometers from the town of Magdelena de Kino in the mining district of Cucurpe, the property covers approximately 1,400 hectares and is surrounded by several gold-silver mining operations including the Alio Gold’s San Francisco mine, Premier Gold’s Mercedes mine, Goldgroup’s Cerro Prieto mine and Agnico Eagle’s recently-acquired Santa Gertrudis mine.
Mineralization types throughout the Cucurpe mining 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. The district has historically been regarded as vein dominated, but recently, open pit mining operations have been developed on disseminated and stockwork style gold mineralization.
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.
In September 2018, Sonoro commenced Phase One of a 10,000-meter reverse-circulation drilling program. A total of 45 reverse circulation holes totaling 4,604 meters were drilled within the property’s Central Zone and confirmed a cluster of eight northwest trending gold-dominant structures and outlined three shallow, bulk-tonnage, gold mineralized zones with supergene oxidized metasedimentary and igneous rock units, all potentially suitable for heap leaching.
The mineralized zones are named after historic mine workings situated within each zone, from east to west, as follows; Abejas, Chinos NW, Japoneses, Los Cuervos, El Quince, Cabeza Blanca, Guadalupe, and El Colorado.
Highlights from Phase One include drill holes SCR-044 and SCR-036 at El Colorado which returned 11.3 grams of AuEq per tonne over 12.2 meters and 4.69 grams per tonne AuEq over 4.6 meters respectively as well as drill hole SCR-033 at Cabeza Blanca which returned 0.95 grams of AuEq per tonne over 12.2 meters and drill hole SCR-030 at Guadalupe which returned 0.77 grams of AuEq per tonne over 22.86 meters.
Results from 19 drill holes in the Cabeza Blanca, El Colorado and Guadalupe zones outline a linear central vein structure with sheeted to stockwork associated mineralization. Results also confirm lateral continuity of over 500 meters for both the Cabeza Blanca zone and its parallel companion, the Guadalupe zone. Furthermore, a high-grade interval of 6.09 meters of 21.5 grams of gold per tonne was cut near an intersection between the Guadalupe and El Colorado zones.
The 19 holes completed in the Japoneses and Cuervos zones indicate one continuous structure extending approximately 1.2 kilometers. Detailed cross sections have been constructed to aid in structural interpretation.
In February 2019, the company commenced Phase Two of its drilling program which further expanded and confirmed new gold-mineralized zones including four new clusters to the northwest of the Central Zone: El Rincon, Gloria, El Boludito, and Veta de Oro.
Drill holes SCR-056 and 057 at the Veta de Oro zone, which is on-strike with the Abejas mineralized zone, returned higher grade gold and silver intercepts and drill hole SCR-054 at the Boludito zone intercepted stockwork-style gold mineralization on strike from the Japoneses zone, indicating it is a likely an extension of this zone. In addition, drill hole SCR-055 demonstrated a probable 300-meter extension of the Buena Suerte zone, which is a developing new zone.
El Rincon and Gloria zones drill holes are located about 1.25 kilometers northwest of the Japoneses zone. At the Rincon zone, drill hole SCR-047 cut four intervals of gold mineralization indicating a new cluster of vein and disseminated gold mineralization.
Drilling one kilometer east of the Japoneses zone identified the easternmost extent of Cerro Caliche’s known mineralization, the Espanola vein zone. Drill hole SCR-068 cut multiple gold mineralized intervals of 6.131 grams of gold and 3.4 grams of silver per tonne over 3.05 meters as well as 1.25 grams of gold and 5.4 grams of silver per tonne over 9.14 meters. To the south of the Japoneses zone, the Chinos Altos vein zone is notable for its pervasive mineralized stockworks which will be tested in more detail in later drilling campaigns.
Sonoro has conducted sufficient infill drilling at the Central Zones surrounding Japoneses and El Colorado to enable the commissioning of a NI-43-101 technical report and several highly-prospective mineralized zones were identified within a 2 kilometer radius from the Central Zones, which will be drilled in future programs to confirm their economic potential.
With almost 90% of the 10,000-meter drill program completed, Sonoro’s objectives of the technical program at Cerro Caliche have mostly been accomplished. Most critically, the program continued to outline shallow low-grade bulk tonnage gold mineralized zones with gold grades and intervals similar to operating heap leach mines in the region.
To date over 6,000 rock chip samples and 80 drill holes totaling 8,796 meters have been completed and assayed by Sonoro Metals. The company has also received and analyzed databases from other operators that conducted exploration on Cerro Caliche since 2007. The combination of historic and current exploration now totals more than 21,400 meters in 196 drill holes, in addition to 10,200 surface samples.
All scientific or technical information contained on this website has been reviewed and approved by Stephen Kenwood, P.Geo., a Director of Sonoro Metals Corp., who is a “Qualified Person” as defined in National Instrument 43-101 of the Canadian Securities Administrators.
CERRO CALICHE EXPLORATION - JUNE 2018
PREPARING TO DRILL CERRO CALICHE - SEPTEMBER 2018
DRILLING AT CERRO CALICHE - OCTOBER - DECEMBER 2018