The Los Ricos North Property consists of 30 concessions in the historical Monte Del Favor Mine area:
- 19 of the concessions are held by GoGold’s wholly-owned Mexican subsidiary Minera Durango Dorado S.A. de C.V. ;
- Five of the concessions are held by GoGold’s wholly-owned Mexican subsidiary TMXI Resources, S.A. de C.V. (“TMXI”) (100%);
- Three by Juan Enrique Michel Arambula (50%) and Enrique Alberto Rivera y Rio Montes de Oca (50%);
- One by Juan Enrique Michel Arambula (33%), Ofelia Alvarez Anaya (33%), and Enrique Alberto Rivera y Rio Montes de Oca (33%);
- One by Enrique Alberto Rivera y Rio Montes de Oca; and
- One by Minera Tiago, S.A. de C.V.
By way of several acquisition and concession agreements (starting on August 22, 2019), GoGold has full control over all of these concessions.
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Summary:
The Los Ricos North (Monte Del Favor) mineralized zones are Neogene (previously Tertiary) age, volcanic-hosted and low-sulphidation epithermal precious metal deposits.
There are five deposits on the Property: Casados, El Favor, La Trini, Mololoa, and El Orito.
At the Property scale, the Gran Cabrera - La Trini – Mololoa - El Favor Deposits are hosted in rhyolites, andesites and aplitic felsic intrusions, and structurally associated with the Monte Del Favor Fault, which trends on an azimuth of 135°. The structural relationships associated with this major fault zone are consistent left-lateral sense of movement. This graben-bounding fault also exhibits evidence of strike-slip movement, which formed shear zones containing anatomizing, horsetail-like shear and fracture features >100 m wide. These smaller-scale structures host the silver-gold mineralization.
The mineralization at La Trini, Mololoa, Casados and El Favor Deposits is dominated by silver and gold, whereas that at El Orito is dominated by silver-lead-zinc-copper sulphides.
La Trini Deposit
The La Trini Deposit occurs at the contact of the El Monte Unit below and the Las Tapias Unit above, along roughly the same stratigraphic horizon as the La Tapatia Unit (intrusion). According to Duncan and Garcia (2019), the mineralization at La Trini is hosted in the aplite felsic intrusion. The mineralization that has been encountered in outcrop, underground workings and in drilling is restricted to a quartz-eye porphyry rhyolite unit and, to some extent, in brecciated, veins and intruded dacite in the footwall of a fault/rhyolite contact. The rhyolite at La Trini is a porphyritic rock with subhedral phenocrysts of feldspar ranging from 1 to 3 mm in length and comprising 15 to 20% of the rock. Quartz is present as bipyramidal, 1 to 3 mm size grains that compose up to 2 to 3% of the rock. The rhyolite is cut by quartz veins containing angular fragments of altered rock.
The La Trini Deposit itself is 650 m long and up to 30 m wide in drilling. Strike changes from west-northwest in the east to north in the west. Dips are 20º north. The deposit is open to expansion by drilling at depth. The host intrusion is a tabular body that occurs within the bounds of a large transverse fault, which has been segmented and rotated into its present position via northwesterly-dipping listric faults.
According to Nebocat (2008), there are some signs of propylitic and stringer alteration in the hanging wall and footwall, respectively. However, the wall rocks lack significant amounts of mineralization.
Mololoa Deposit
The Mololoa Deposit is located between the La Trini Deposit in the north and the El Favor Deposit in the south. Mololoa, like La Trini, is hosted in the Las Tapias Unit, probably a felsic intrusion. The Mololoa Deposit is approximately 1,000 m long and up to 12 m wide in drilling. Westwards, the Mololoa Vein system strikes roughly north for 400 m and then changes to westerly for 500 m. Dips are 30º east or north. The Mololoa Deposit appears to thin down-dip, though may be open to expansion by drilling at depth.
Casados Deposit
The Casados Deposit occurs approximately 3,000 m to the west of the Mololoa Deposit, between La Trini Deposit to the north and El Favor Deposits to the south. Casados comes to surface in a topographic low.
The Casados Deposit is hosted in the Las Tapias Unit. The most abundant rock type at Casados is andesit, specifically flows, porphyry intrusions, tuffs and undifferentiated andesites, which are mostly agglomerates.
The Casados Deposit is approximately 1,000 m long and up to 70 m wide in drilling. The deposit strikes west-northwest and dips 65º north. According to Asher (1977), a zone of silicification up to 50 m wide envelopes the Casados Vein and this resistant outcrop forms a steep ridge along the strike of the vein, particularly on the north or hanging wall side. Northwesttrending faults cut the volcanic rocks and intersect and offset the Casados Vein. To the west, the Casados Vein terminates against a fault of the same system; a short parallel structure shows some mineralization in the same vicinity. To the east, a northwest fault terminates the Casados Vein, however, the associated silicification continues northward. The Casados Deposit is open to expansion by drilling at depth and might perhaps be an extension of the Mololoa Deposit to the east.
El Favor Deposit
El Favor is the southernmost deposit included in the Mineral Resource Estimate presented in Section 14 of this Report. The El Favor Deposit comes to surface as a topographic low and was the site of the historical El Monte de Favor Mine. The El Favor Deposit is hosted in the Las Tapias Unit. The silver-gold mineralization is hosted by quartz veins and fault breccia zones (Walton, 2003) that collectively are up to 70 m wide. Westwards, the mineralized vein system deposit strikes northwesterly and dips 45º north, and then strikes northeasterly. The El Favor Deposit is open to expansion by drilling at depth and to the east along strike.
El Orito Deposit
The El Orito Deposit is located approximately 1,200 m to the west of the El Favor Deposit. El Orito comes to surface in a slight topographic low on the south side of a hill. The El Orito Deposit is hosted mainly in the El Monte Unit to the east and in the Las Tapias Unit in the west. Outcrops of silver-gold mineralized quartz veins occur within a 750 m long and 35 m wide zone of silicification and epithermal alteration. In drilling, the Deposit is approximately 1,000 m long and up to 75 m wide. The El Orito Vein system strikes northwest and dips 60º north to vertical. The vein system thins down-dip, however, still appears to be open to expansion by drilling at depth. The El Orito Deposit is possibly an along strike extension of the El Favor Deposit. However, the surface topography is 400 to 500 m lower at El Orito than El Favor, potentially exposing a deeper level of the mineral system, which has silver-base metal mineralization and therefore appears to be relatively unique on the Los Ricos North Property
MINERALIZATION
The silver-gold mineralization in the La Trini, Mololoa, Casados and El Favor Deposits is similar to each other (relatively precious metal rich and base metal and sulphide poor), and therefore described collectively below. In contrast, the silver-gold-lead-zinc-copper sulphide mineralization at El Orito is distinctly different (relatively gold-poor and base metal-rich) and is described separately.
Silver-Gold Mineralization
The La Trini, Mololoa, Casados and El Favor Deposits are classified as low-sulphidation, open space filling, epithermal quartz veins containing dominantly silver sulphides, related oxide minerals and gold (Walton, 2003; Nebocat, 2008). According to Duncan and Garcia (2019), mineralization consists of both quartz veins and veinlets and disseminated styles, composed of mainly finely disseminated pyrite, argentite, native silver, cerargerite and minor amounts of hessite (silver telluride). Galena is also present (at least at El Favor) (Walton, 2003). However, the total sulphide content is generally low in these four mineralized zones, consistent with classification as "low sulphidation" epithermal silver-gold deposits. Manganese minerals may be present, particularly at the Casados Deposit.
Silver-Base Metals Mineralization
The El Orito Deposit is relatively unique at Los Ricos North, in that it appears that silver and base metal sulphides, however, not much gold, are present. The base metals are zinc, lead and copper. In addition to pyrite, the sulphide minerals present are chalcopyrite, galena and sphalerite. These sulphide minerals also occur as bands, patches and disseminations in structurally-controlled quartz.