Overview

Mine Type	Open Pit
Status	Care and Maintenance
Commodities	Gold Silver
Mining Method	Truck & Shovel / Loader
Production Start	...
Snapshot	The San Francisco operation is comprised of two previously mined open pits,San Francisco and La Chicharra with heap leach processing facilities. On February 16, 2023, Magna Gold Corp. announced that its subsidiary, Molimentales del Noroeste S.A. de C.V. has received Notices of Claims from three of its creditors in Mexico. On March 27, 2023, Magna Gold Corp. announced that it was granted an Initial Order pursuant to the Companies' Creditors Arrangement Act by the Ontario Superior Court of Justice. The Initial Order, among other things authorizes Magna Gold to incur no further expenses in relation to any filings and disclosures. Management of Magna Gold and Molimentales remain responsible for the day-to-day operations, under the general oversight of the KSV Restructuring Inc. and the Concurso Court. No mining is being conducted at the San Francisco mine. The goal of the care and maintenance activities is to complete a safe shut down.

Deposit type

• Vein / narrow vein
• Mesothermal

Summary:

PROPERTY GEOLOGY
The San Francisco property lies in a portion of the Mojave-Sonora megashear belt characterized by the presence of Precambrian to Tertiary age rocks represented by different grades of deformation and metamorphism as evidenced in the field by imbricate tectonic laminates. The rocks principally involved in the process of deformation and associated with the gold mineralization in the region are of Precambrian, Jurassic and Cretaceous age.

The metamorphic rocks are intruded by a Tertiary igneous package, which includes leucocratic granite with visible feldspar and quartz, and is porphyritic to gneissic in texture. It appears that the granite was emplaced along low angle northwest-southeast shear zones in the system which developed between an older gabbro and the metamorphic sequence. This is the reason that in some places the granite bodies appear as stratiform lenses that vary in width from centimetres to more than 40 m and are subparallel to the foliation. It is seen, however, that the emplacement of leucocratic granite also favours the N30°W fault system, causing the granite to take an elongated form, principally in direction N60°W, but with extensions along the N30°W system.

MINERALIZATION
The San Francisco property is located within the Sierra Madre Occidental metallogenic province which extends along western Mexico from the state of Sonora, south to the state of Jalisco. In the state of Sonora, the most important metal produced in the Sierra Madre province is copper, with the Cananea porphyry copper deposit being the most well-known. Gold and silver projects are next in importance and are hosted mainly in sedimentary rocks and brecciated volcanic domes.

At the San Francisco Project, gold occurs principally as free gold and occasionally as electrum. Gold is found, in decreasing abundance, with goethite after pyrite, with pyrite and, to a much lesser extent, with quartz, galena and petzite (Ag3AuTe2). Although it is clear that the gold was deposited at the same time as the sulphides, the paragenetic relationships are not well understood. There is the possibility that some secondary remobilization may have occurred as evidenced by minor amounts of gold occurring in irregular forms along with or on top of drusy quartz (Prenn, 1995).

The gold occurs in a granitic gneiss and the presence of pyrite (or goethite after pyrite) may be an indication of gold. Stockwork quartz veinlets, some with tourmaline, also exist in the mineralized zone. However, the presence of quartz, even with tourmaline, is not necessarily an indication of the presence of gold. Quartz veinlets with tourmaline but without gold mineralization were found hundreds of metres away from the San Francisco deposit. Alvarez (in Prenn, 1995) suggested that some tourmaline was part of the mineralizing system, but could be distinguished from the tourmaline found elsewhere.

DEPOSIT TYPES
At the San Francisco Project, Alio was targeting large volume, low-grade disseminated gold deposits contained within leucocratic granite, granite-gneiss and gneiss and schist horizons. Leucocratic granite and gneiss are the main rocks hosting the gold mineralization.

The gold mineralization occurs in a series of west-northwest to east-northeast trending quartztourmaline veins and veinlets that lie sub-parallel to the local lithology and foliation trends, dipping to the southwest, within the more brittle rocks such as the leucocratic granite and more felsic lithologies within the Precambrian sequence. Extensive studies of the veins and alteration describe the mineralization as mesothermal/orogenic in style, but with a potential link to magmatic fluids and an intrusive source (Calmus et al., 1992; Luna and Gastelum, 1992; Perez Segura, 1992; Perezsegura et al., 1996; Perez Segura, 2008; Albinson, 1997; Poulsen and Mortensen, 2008).

Micon has conducted a number of discussions with Alio personnel during its prior site visits to the mine and in Hermosillo and notes that the exploration programs at the San Francisco Project were planned and executed on the basis of the deposit models discussed above. Micon has also observed the various stages of the drilling programs during a number of site visits at the San Francisco Project since 2005 and notes that those programs were always been conducted according to the deposit model which has been proposed for the Project.

Mining Methods

- subscription is required.

Comminution

Crushers and Mills

- subscription is required.

Processing

- subscription is required.

Production

Commodity	Units	2022	2021	2020	2019	2018	2017	2016	2015
Gold	oz	....	....	....	36,461	53,990	83,558	100,322	93,353
Silver	oz	....	....	....	16,672	24,774	38,911	56,326	52,047

Operational metrics

Metrics	2022	2021	2020	2019	2018	2017	2016	2015
Daily mining rate	....	....	....		63,887 t	71,113 t	61,076 t	95,582 t
Daily processing rate	....	....	....	16,864 t	17,839 t	20,649 t	20,909 t	23,147 t
Stripping / waste ratio	....	....	....		1.99	2.71	2	3.43
Ore tonnes mined	....	....	....		6,046 kt	6,997 kt	7,457,484 t	7,880,292 t
Waste	....	....	....		15,510 kt	18,960 kt	14,896,386 t	27,007,221 t
Total tonnes mined	....	....	....		23,318 kt	25,956 kt	22,353,870 t	34,887,513 t
Tonnes processed	....	....	....	6,155 kt	6,511 kt	7,537 kt	7,652,642 t	8,448,731 t