Mineralization
The Ying Property contains multiple mesothermal silver-lead-zinc-rich quartz-carbonate veins in steeply-dipping fault-fissure zones which cut Archean gneiss and greenstone. To date, significant mineralization has been defined or developed in at least 308 discrete vein structures, and many other smaller veins have been found but not as yet well explored.

Structurally, the vein systems throughout the district are all somewhat similar in that they occur as sets of veins of generally similar orientation enclosed by fault-fissure zones which trend most commonly northeast-southwest, less commonly north-south, and rarely northwest-southeast. The structures extend for hundreds to a few thousand metres along strike. They are often filled by altered andesite or diabase dikes together with quartz-carbonate veins or as discrete zones of altered bedrock (mainly gneiss) associated with local selvages of quartz-carbonate veinlets. From one-third to one-half of the structures exposed at the surface are conspicuously mineralized as well as altered.

The vein systems consist of narrow, tabular or splayed veins, often occurring as sets of parallel and offset veins. The veins thin and thicken abruptly along the structures in classic “pinch-and-swell” fashion with widths varying from a few centimetres up to a few metres. “Swells” formed in structural dilatant zones along the veins often forming mineralized “shoots”. At the SGX mine, these sh ........

The Ying Mining District has been intermittently mined over many years by small-scale, local miners. Silvercorp commenced mining at its Ying property (SGX mine) in April 2006. Its current mining activities continue to be focused at the SGX mine, but now also include the HZG (a satellite deposit to SGX), HPG, TLP, LME, and LMW mines, and the DCG project.

Underground access to each of the mines in the steeply-sloped, mountainous district is via adits at various elevations, inclined haulageways, shaft / internal shafts (winzes), and declines (ramps).

The mines are developed using trackless equipment – 20 t trucks and single-boom jumbos; small, conventional tracked equipment – electric/diesel locomotives, rail cars, electric rocker shovels; and pneumatic hand-held drills. At most of TLP, four adits of SGX, part of LME and part of LMW mines, small tricycle trucks with a payload of up to three tonnes each are used to haul ore to surface. These tricycle trucks are being gradually replaced by rail cars in all mines except for TLP.

The global extraction sequence is top-down between levels, and generally outwards from the central shaft or main access location. The stope extraction sequence is bottom-up, with shrinkage and resuing being the main mining methods. Jacklegs are used in stope blast drilling. In-stope ore handling is by hand-carting / hand-shoveling to specially manufactured steel-lined ore passes for resuing stopes, and by gravity to draw po ........

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Silvercorp runs two processing plants, Plant 1 (also known as No.1 Mill) and Plant 2 (also known as No.2 Mill), for the Ying operations, with a total design capacity of 1,600 tpd (prior to October 2011), and then 2,600 tpd after October 2011 when expansion phase II was completed. The two plants are situated within 2 km of each other.

Both plants were designed based on the lab tests completed by HNMRI in 2005.
• Plant 1 (Xiayu Plant, 600 tpd) has been in operation since March 2007.
• Plant 2 (Zhuangtou Plant): (1) Phase I (1,000 tpd) has been in production since December 2009; (2) Phase II (1,000 tpd) has been in production since October 2011 when expansion of another parallel flotation bank was completed. The total design processing capacity is now 2,000 tpd.
• Total processing capacity for Plants 1 and 2 in 2020 is 2,600 tpd of ore.

Ore supply
Ore from the Ying mines is shipped via barge and/or truck to the milling flotation Plants ........