Location and Infrastructure

The Segovia Operations are located 180 kilometres northeast of Medellín in the Segovia-Remedios mining district of Antioquia, Colombia. Segovia is a multi-million-ounce high-grade gold operation that has been producing gold for more than 150 years. The Segovia mining title covers an area of 2,906 hectares and includes three underground mines – El Silencio, Sandra K, and Providencia – and a gravity concentration and gold flotation process plant (the Maria Dama plant). The Carla mine, which has been operating since 2021, is located to the south of the Segovia operations and the mining title covers 567 hectares.

The Segovia Operations are supported by excellent infrastructure including a connection to the national power grid. Water is sourced from underground dewatering and rainwater, and the property is accessible by a 225 kilometre fully paved road from Medellín. Air access is by a 30-minute charter flight from Medellín to Otú, 15 kilometres south of Segovia. A large pool of skilled labour is available in the nearby towns of Segovia and Remedios.

Mining and Processing

Mining at the Segovia Operations is sourced from four underground mines using room and pillar or cut and fill mining methods, with the ore hoisted to the surface. Since 2017, the operation also incorporates the processing of ore provided by local informal miners through an artisanal mining model (ASM), which represented 12% and 16% of gold production in 2020 and 2021, respectively. Aris Mining has agreements with 63 third party ASM groups who mine in designated areas. Aris Mining pays for the recovered gold at a fixed price, processes the ore at the Maria Dama plant, and sells the gold/silver.

Ore is processed through the Maria Dama process plant using crushing, grinding, gravity concentration, gold flotation, concentrate regrinding, concentrate cyanidation, Merrill-Crowe zinc precipitation and refining of both the zinc precipitate and gravity concentrate to produce a final gold/silver doré product. The plant is currently undergoing an expansion to increase capacity from 1,500 tonnes per day (tpd) to 2,000 tpd.

A new 200 tpd polymetallic processing plant was built in 2021 to recover zinc, lead, gold and silver from tailings to provide an additional source of cash flow from the mining operations. Tailings from the Maria Dama plant are treated through a filter press operation that produces dry stack tailings which are stored at the El Chocho tailings storage facility.

Geology and Mineralization

Gold mineralization at Segovia occurs in mesothermal quartz-sulfide veins hosted by granodiorites of the Segovia Batholith. The well-known, partially exploited veins dip at approximately 30° to the east or northeast. There are also a number of steeply dipping quartz veins at Las Verticales in the western part of the concession, where inferred mineral resources have been estimated.

The El Silencio mine has a strike of 2.7 kilometres, and extends down dip by 900 metres, with additional structures still being identified with drilling. The Providencia mine has a known strike length of approximately two kilometres and a down dip extent that ranges from 690 metres to greater than 1.3 kilometres. Providencia is still open at depth. The Sandra K vein strikes for two kilometres and extends 700 metres to 900 metres down dip, and is open at depth and along strike. Carla is a new mine and has a strike of 900 metres and a down dip extent of 400 metres to 750 metres, and is still open along strike and at depth. Mineral resources have also been estimated at the historical Vera mine.

Exploration

Aris Mining has extensive annual exploration and drilling programs at Segovia to identify new resources to expand production. Segovia has six consecutive years of replacing mined ounces with new resources.

Aris Mining has a robust 2022 diamond drilling campaign comprised of 91,000 metres. Of this, up to 52,000 metres will be in-mine and near-mine drilling, 15,000 metres will be underground infill drilling at the four producing mines, and 24,000 metres will be brownfield drilling at high-priority targets within the other 24 known veins where mining is not currently under way.

Additionally, the geology teams have ongoing programs of digitizing historical sampling data and collecting new channel sampling at historical mines to define additional exploration targets and to connect data to deeper structures.