The Property consists of three mining rights (PELs) granted to Minera Granville S.R.L., a private Bolivian company is 100% owned by Bolivian nationals, by the Bolivian authority AJAM (Mining Administrative Jurisdictional Authority). As the Property is located within 50 kilometres of international borders where foreign companies or foreigners are not permitted to have ownership of the land and right of mineral, Granville remains the holder of all licenses, permits and rights granted to it by Bolivian authorities.
In April 2021, New Pacific Metals (NPM) signed a joint venture agreement or the Mining Association Contract (MAC) with Minera Granville to conduct the geological and mining works related to these PELs. According to the agreement, New Pacific Metals has acquired a 98% interest in the Carangas Project. The agreement has a term of 30 years and is renewable for another 15 years.
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Summary:
The project area mineralization is a silver-gold polymetallic epithermal deposit of low-intermediate sulfidation associated with a rhyolitic maar diatreme cutting into volcanic and volcaniclastic country rocks of Oligocene to Miocene age. The upper portion of the Carangas deposit represents a low sulfidation zone, characterized by argillic and propylitic alterations as well as mineralization of sulfide minerals of silver, lead and zinc featured by argentiferous galena, silver sulfosalts, minor native silver, galena, sphalerite, and various gangue minerals, including crustiform-coloform chalcedony, banded chalcedony, smectite, zeolites, carbonates, and chlorite.
To depth, the low sulfidation zone gradually transitions into an intermediate sulfidation zone at a depth of approximately 200 m with sericitic and phyllic alteration and mineralization dominated by gold and a small amount of copper, represented by minerals of electrum, chalcopyrite, pyrite and native gold. Recent microscopic studies conducted in 2022 have further identified the presence of other copper minerals, including enargite (Cu3AsS4) and famatinite (Cu3SbS4). The zone of intermediate sulfidation extends from a depth of approximately about 200 m to a depth of more than 700 m. The mineralization in this zone is mainly controlled by the diatreme structure and the intrusion of rhyolite.
Geology
The Carangas deposit is located at the southwest corner of the Carangas basin, a caldera in the Carangas Exterior-Caldera system. Geomorphologically, it consists of two prominent hills, namely the West Dome and the East Dome, and a valley in between called the Central Valley. The two domes are more than 100 m above the surrounding fluvial plains. Near the south end of the Central Valley, a small, outcropped hill is known as the South Dome. Historically, the West Dome is referred to as Espiritu Santo Hill while the East Dome as San Antonio Hill.
The upper part of the diatreme is exposed on the top of the West Dome, and three types of rock were identified: hydrothermal breccia, heterolithic breccia and sandy tuff. To the west of the diatreme breccias, spotty outcrops of dacitic to rhyolitic dykes with flow banding textures are exposed on surface. The rhyolite dykes roughly strike north-northwest direction, and the flow bandings generally dipping west at high angles.
The Central Valley is fully covered by young fluvial sediments from a few meters up to 50 m thick. Logging of drill cores indicates the rock types beneath the valley are mainly altered phreatic breccia and lithic tuff. To the south, at the South Dome, the outcropped rocks are mainly altered phreatic breccia. Rocks in the East Dome are mainly altered lithic tuffs, likely the overlying phreatic breccias of diatreme already eroded.
Mineralization
The mineralization of Carangas consists of a diverse suite of metallic sulfide minerals and gangue minerals, occurring as veins/veinlets, breccia fillings and dissemination. The Company had a joint research program with the San Andrés Major University in La Paz (SAMU) to study the mineralization style and alteration of the Carangas deposit. At least three hydrothermal mineralization phases and one supergene event are identified in the project area.
The mineralization is controlled by the temperature and pressure of the hydrothermal system, i.e., the depth from ground surface or the distance from the source of heat generated by rhyolitic intrusions. Three zones of mineralization can be recognized as zoning of different metals. The Upper Silver Zone is near the surface and dominated by silver plus a moderate amount of lead and zinc. Below the upper zone, the Middle Zinc Zone is dominated by zinc plus minor silver and lead. The Lower Gold Zone is dominated by gold plus a small amount of silver, copper and zinc.
Upper Silver Zone
The Upper Silver Zone is formed in a relatively low temperature and pressure environment approximately within 150 - 200 m from the surface in an area of about 1,000 m long in an east-west direction by 800 m wide in a north-south direction, spanning across the entire area of West Dome-Central Valley- East Dome-South Dome of Carangas deposit. It is interpreted as the distal phase of hydrothermal alteration and mineralization system arising from the rhyolitic intrusions at the depth of the Central Valley area.
At the top area of West Dome, there is a mineralized horizon of up to 50 m thick, composed of hydrothermal breccia of altered rhyolite clasts cemented by low-temperature silica of chalcedony, heterolithic breccia comprised of clasts of various lithologies and a matrix of fine debris of similar lithology as the clasts as well as unlithified loose sandy tuff layers and lenses with sedimentary beddings. These three types of rocks are intercalated with each other. The hydrothermal breccia generally contains a higher grade of silver compared to heterolithic breccia and sandy tuff. When the cementing chalcedony of hydrothermal breccia looks grey or dark in colour, it may contain silver up to 1,000 ppm. Due to erosion, the current thickness of this silver-lead horizon is from a few meters up to 50 m thick.
Middle Zinc Zone
When the temperature and pressure of the hydrothermal system become higher at depth below the Upper Silver Zone, grades of silver and lead in mineralization drop. In contrast, zinc grades rise with low grades of copper and gold locally in the lower portion of the zone.
Mineralization in the Middle Zinc Zone is characterized by the dissemination of marmatite and veining of honey sphalerite, galena, chalcopyrite, pyrite, siderite and small amount of silver sulfosalts. This zinc-dominated zone is generally from 150 m below surface with a thickness of tens of meters up to 150 m. The Zinc Zone is interpreted to be the peripheral zone close to the core Gold Zone formed in a higher temperature/pressure environment in the vicinity of rhyolitic intrusions.
Lower Gold Zone
The Lower Gold Zone lies below the Middle Zinc Zone. Mineralization in this zone is characterized by the dissemination of pyrite and sulfides veining of pyrite and chalcopyrite plus a small amount of galena and sphalerite hosted in strongly argillic-sericitic altered phreatic breccia and rhyolite intrusions. This gold zone generally begins from a depth of 200 m. It extends to a depth of more than 800 m with a lateral extent up to 400 m wide, mostly confined to the diatreme pipe body and partially extending laterally into surrounding older volcanoclastic rocks. ASMIN lab studies indicate that gold occurs mainly in the form of free electrum, in minor amounts as native gold and very sparsely as Fe (Au) sulfides, Au-Ag sulfides and galena (Au). The grade of gold generally gets higher with depth and is highest around the elevation of 3500 m in the middle part of the gold zone. The gold grade declines to a further depth, but the copper grade gets relatively higher than in the upper portion. This zoning of metals is likely induced by the higher temperature/pressure environment of hydrothermal activities at depth.
Gold mineralization is fully controlled by the diatreme pipe structure, which is associated with rhyolitic dyke intrusions and perfectly overlays with the IP chargeability anomaly in the Central Valley area. This coincidence may imply that other IP chargeability anomalies beyond the drilled area could be promising targets of additional mineral potential and warrant drill testing in the future.