Xiaoyingpan Mine (Xiaoyinpan Mine; Zhangjiakou Mine), Xiaozhangjiakou gold field, Xuanhua District, Zhangjiakou, Hebei, Chinai

Regional Level Types
Xiaoyingpan Mine (Xiaoyinpan Mine; Zhangjiakou Mine)	Mine
Xiaozhangjiakou gold field	Ore Field
Xuanhua District	District
Zhangjiakou	Prefecture-level City
Hebei	Province
China	Country

Alkaline complex-hosted gold deposit in amphibole plagioclase leptynite, amphibolite and granulite of the Archean Shanggan Group. The Hercynian Shuiquangou Alkaline Complex, Yanshanian granite stocks and some dikes occur adjacent to the mine. The alkaline complex is hosted in metamorphic strata of the Shanggan Group, with an exposed area of 340 km2, 55 km long in E-W direction and 5-8 km wide from north to south. The main rock types in the alkaline complex are alkaline feldspar syenite, quartz alkaline feldspar syenite, pyroxene amphibole syenite, amphibole alkaline feldspar syenite, pyroxene amphibole monzonite and amphibole monzonite. The deposit is controlled by NE-trending compressive faults. The orebodies are stratiform, lenticular and lensoid. There are three deposition types: (1) gold-bearing quartz veins (82%), (2) gold-bearing K feldspar-quartz veins (15%), and (3) altered rock type (3%). The ore textures are typically idiomorphic and xenomorphic, metasomatic relics and metasomatic pseudomorphs. The minerals occur in disseminations, masses, breccia and honey-combs. Alterations include sericitization, silicification and carbonatization.

The large Xiaoyingpan Te-rich Au deposit has a proven reserve of ∼80 t Au (Jinyuan Gold Co., Ltd) and is situated to the southwest of Zhang-Xuan ore district. It is hosted within amphibolite- to granulite-facies rocks of Jianhegou and Huajiaying Formation, Neoarchean Sanggan Group, which mainly consist of plagioclase-amphibole gneiss, granulite, amphibolite and migmatite. Since this deposit was discovered in 1965, ∼30 mineralized quartz veins have been identified, accounting for main mineralization style. The auriferous quartz veins occur as layered to lenticular bodies exhibiting two distinct morphological types: subhorizontal veins with dip angles <30° and subordinate steeply dipping varieties (60–85° dip). Individual veins range in thickness from 0.2 to 10 m averaging at ∼2 m. Gold grades show a large variation of 1.5 to 30 g/t with an average of ∼12 g/t and locally reach 154 g/t. Four paragenetic stages can be recognized. Stage I is characterized by K-feldspar-quartz-specularite ± pyrite assemblages. Stage II and III are featured by the presence of abundant pyrite and native gold, with stage III containing abundant tellurides, galena and minor chalcopyrite. Gangue minerals in these two stages are dominated by quartz as well as minor sericite and chlorite. Stage IV contains quartz-calcite assemblages without sulfides.

Other Regions, Features and Areas containing this locality

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