Nyanga North Shear Zone Gold - Base Metal Prospect
Sutter Mining (Private) Limited a wholly owned Zimbabwe subsidiary of Zephyr Minerals Ltd. has staked two Special Blocks totaling 201 hectares with potential for gold and base metals in the northeastern part of the Umkondo Basin of Zimbabwe (See Fig. 1). A Special Block is a mining claim up to 150 hectares in size and entitles the holder to explore for, and mine any minerals that may be discovered and deemed economic. In the event only gold is discovered, regulations require the Special Blocks to be converted into gold claims. This is a straight forward process that requires subdividing the Special Blocks into 10 hectare, surveyed gold Claims. The Special Blocks are renewable annually by paying annual fees as gazetted by the government. The two staked Special Blocks cover an area of a postulated shear zone which is interpreted to be the eastern extension of the gossanous zone recently mined for gold by local artisanal miners as evidenced by numerous small pits (See Photos 1 & 2).
The project is located in north-eastern Zimbabwe in the province of Manicaland near the border with Mozambique centered on 17 degrees 40 minutes and 11 seconds South and 33 degrees 00 minutes and 45 seconds East. The topography is hilly with elevations above the valley floor in the 100 to 150 meter range. The majority of the project area is rock outcrop with minor forested and farming areas at lower elevations. The majority of the project area is rock outcrop with minor forested and farming areas at lower elevations. The Gairezi River immediately east of the Special Blocks marks the border of Zimbabwe with Mozambique (See Fig. 3).
Geologically the area is part of the N-S trending Gairezi Segment of the Umkondo Basin (Payne 1989 and Stocklmayer 1979), a Proterozoic age sedimentary basin, which was deposited in a braided stream and shallow marine environment. The sedimentary units underwent moderate grade metamorphism and are manifested in the area as quartz mica schists and quartzites.
Gold & Copper Prospectivity of the Umkondo Basin
Until recent discoveries by artisanal miners of hydrothermal gold deposits in the Umkondo Basin, this terrane had not been considered prospective for gold mineralization. Previously only copper mineralization had been noted in the Umkondo basin. Traditionally, potential for gold deposits in Zimbabwe was considered to be principally in the Archean granite-greenstone terrane, hence geological settings outside this terrane, like the Umkondo Basin received little attention from mining companies. The Umkondo Basin is now however, proving to be a new frontier for gold exploration following the discovery and mining by artisanal miners of gold at several localities. Despite these recent important developments, the Nyanga area of the Umkondo Basin has not yet been drilled nor targeted with systematic mineral exploration programs.
The Nyanga prospect was staked based on artisanal eluvium gold mining from a gossanous scree slope approximately 370 meters west of the western boundary of the Company’s Special Blocks (See Fig. 2). Locals have been mining gossanous scree over an area measuring approximately 240 m by 60 m from the side of a 100 meter high hill since approximately 2014 (See Fig. 3 & Photos 1 & 2). As interpreted from satellite imagery, a 2 km long, east-west trending shear zone traces the trend of the gossanous scree zone to the east into the Company’s Special Blocks. Based on the extensive eluvium mining at the western extremity of the postulated shear zone, this is undoubtedly a highly prospective gold exploration target. An initial, low cost exploration program would entail soil sampling and geological mapping to characterize the postulated shear zone. If initial results warrant, trenching to expose the shear zone and/or drilling would be the next phase of work.
Figure 1: Zimbabwe Geological Map
Figure 2: Google image of the Nyanga North Prospect
Figure 3: Google image close-up of the gossanous scree at the Nyanga North Prospect
Photo 1: Looking east at the gossanous scree. Note that there is only minor artisanal mining due to the
lack of water. This photo was taken in September at the end of the dry season.
Photo 2:Close-up of the gossanous scree showing pits. Notice the water line at
the bottom of the photo.
Payne C.D.B, 1984 The geology of the sediments of the Umkondo Group in Nyanga area. Unpublished BSC Hons, University of Zimbabwe.
Stagman J.G., 1977. An Outline of the Geology Rhodesia, Bulletin 80, Rhodesia Geological Survey.
Stocklmayer V.R., 1978. The Geology of Inyanga area, Bulletin 79, Rhodesia Geological Survey.