Operations
SGX / HZG Mines (Ying Mining District)
Introduction
SGX
- Flagship silver-lead-zinc mine
- Operates under the Yuelianggou Mining License
- Largest of Silvercorp’s seven underground mining operations at Ying
- Property acquired March 2004 and brought into production following two years of exploration and development on April 1, 2006
HZG
- Satellite silver-lead mine with portals located ~4 km south of SGX
- Declared production in 2011
Both SGX and HZG are 100% owned by Henan Found Mining Ltd., a sino-foreign cooperative JV company owned 77.5% by Silvercorp and 22.5% by Henan Non-Ferrous Geological & Mineral Resources Co. Ltd. Henan Found operates under a 30-year business license issued by the Chinese government and has been granted all necessary permits.
MINING
SGX And HZG Mines Quick Facts
| SGX | HZG | |
| Mine type | Ramp and shaft
supported underground |
Ramp supported
underground |
| Mining method | Re-suing and shrinkage | Re-suing and shrinkage |
| Reserve tonnage1 | 5,230 kt | 730 kt |
| Reserve grades1 | 249 g/t silver
0.03 g/t gold 4.76% lead 2.18% zinc |
348 g/t silver
0.93% lead |
| % of Ying’s LOM ore production | 42% | 6% |
| Primary metal | Silver | Silver |
| By-product metals | Lead, zinc, gold | Lead |
1 Mineral reserves estimate as of December 31, 2021.
Exploration and Geology
Recent Work/ Highlights
Silvercorp completed 52,634 m of drilling in 327 diamond drill holes at SGX from July 1 to December 31, 2021.
High-grade silver-lead-zinc intercepts at the SGX mine:
- Hole ZK02AS6E1007 intersected a 3.19 m interval (1.35 m true width) of vein S31 grading 2,532 g/t silver, 0.69% lead, 14.38% zinc, 0.05 g/t gold, and 0.12% copper from 58.35 m depth, at an elevation of 372 m.
- Hole ZK12S7001 intersected a 2.02 m interval (1.65 m true width) of vein S7a1 grading 1,315 g/t silver, 14.36% lead, 0.84% zinc, 0.24 g/t gold, and 0.23% copper from 161.50 m depth, at an elevation of 300 m.
High-grade gold-silver intercepts at the SGX mine:
- Hole ZK68AS16W002 intersected a 5.38 m interval (5.36 m true width) of vein S16W grading 52 g/t silver, 1.08% lead, 0.39% zinc, 3.93 g/t gold, and 0.01% copper from 37.67 m depth, at an elevation of 340 m.
- Hole ZK74S16W08 intersected a 1.74 m interval (1.58 m true width) of vein S16E3 grading 3 g/t silver, 0.01% lead, 0.01% zinc, 5.57 g/t gold, and 0.01% copper from 92.90 m depth, at an elevation of 246 m.
Geological Background
Mineralization at SGX is defined by at least 75 veins within eight major and two minor vein systems. The five largest veins, S19, S8, S2, S7, and S7_1, contain about 33% of SGX’s current mineral resources. Mapping and sampling results showed that ~30% of the vein material is mineralized with massive, semi-massive, veinlet and disseminated galena and sphalerite. Vein widths range from 0.3 m to over 5 m, averaging 0.69 m. Other metallic constituents include small amounts of pyrite, chalcopyrite, hematite, and very small amounts of wire silver, silver-bearing sulfosalts (mainly pyrargyrite), silver-bearing tetrahedrite (freibergite) and possibly acanthite (silver sulphide). The minerals are confined to the veins where they occur as massive accumulations or disseminations. Galena often occurs as massive tabular lenses comprised of coarsely crystalline aggregates or fine-grained granular “steel galena” bodies, which can be up to 1.0 m thick and over 100 m along vertical and horizontal dimensions. Sphalerite, in its dark-coloured, iron-rich variety colloquially known as “blackjack”, occurs with the galena as coarse bands or aggregates. Alternating bands of galena, sphalerite, pyrite, and quartz are common near the vein margins.
At least 21 silver-lead-zinc veins have been identified at the HZG satellite mine, mostly trending NE-SW and bending NNE-SSW toward the western margin. The five largest veins, HZ26, HZ20, HZ22, HZ22E, and HZ15, contain about 59% of HZG’s current mineral resources. Sampling and drilling results indicate that 14% to 23% of the vein material is mineralized, ranging from 0.30 to 1.44 m in width, averaging 0.55 m. Compared to other veins in the district, HZG veins contain distinctly more copper (in chalcopyrite and tetrahedrite) but lower zinc. Tetrahedrite commonly forms massive lenses, likely filling tension gashes that are distributed in relay-like fashion near the vein margins and in ladder-like fashion near the centre of the veins. Chalcopyrite occurs as disseminated crystals in the gangue and in the tetrahedrite. Other sulphides include galena (up to several percent locally) and pyrite.
