The Yingqian deposit in the central GUMCA (Gulonggang uranium mineralization concentration area) is the largest uranium deposit in the region. The Neoproterozoic metasediments are the basement in the deposit, which have been found through drilling. Granites in the Yingqian deposit are mostly medium–coarse grained biotite granite, with the local occurrence of fine grained two-mica granite.
The orebodies of the Yingqian deposit are located in fractures, especially the conjunction between the NE- and NS-trending faults. The orebodies are generally present as veins with some as lens, veinlets and vesicles. Most ore veins are NE-trending with high dipping angles (>70°). The maximum thickness of the orebodies is about 24.2 m, and the ore grade can be up to 0.37 %. Current drilling indicates that the most significant uranium mineralization occurs at the depth of 240–420 m.

It is the largest granite-related uranium deposit in the district, with a total uranium resource exceeding 1,000 t at an average grade of ∼0.15% . The deposit is underlain by a Neoproterozoic metamorphic basement, composed mainly of dark gray to light green, medium- to thick-bedded metasandstone and metatuff. Magmatic rocks in the district comprise Late Jurassic granites, with the ore-hosting rocks consisting predominantly of medium- to coarse-grained porphyritic biotite granite, and locally of medium- to fine-grained biotite granite. Mineralization mainly occurs as veins and lenticular orebodies, with local veinlet-network and cavity-filling forms. Most orebodies are developed at depths of 240–420 m. Hydrothermal mineralization at the Yingqian uranium deposit can be divided into four successive stages. Stage I is represented by an early quartz–fluorite–pyrite assemblage, in which quartz (Q1) occurs as very fine-grained particles, typically smaller than 10 μm. Veins of Q1 are commonly cut through by later, coarse comb-textured quartz (Q2), indicating overprinting by a subsequent hydrothermal event. Stage II comprises quartz (Q2), pyrite (Py2), fluorite (Fl2), calcite (Cal1) and pitchblende, constituting an important mineralizing episode. Quartz in this stage is generally coarse grained and commonly displays a comb texture, with crystal sizes typically exceeding 200 μm. Stage III consists mainly of quartz (Q3), pyrite (Py3), hematite, fluorite (Fl3), pitchblende, rutile, calcite, sphalerite and galena. Compared with Q2, Q3 is distinctly finer grained, generally ranging from 50 to 100 μm. Stage IV is a late quartz–pyrite–calcite assemblage characterized by quartz (Q4), pyrite (Py4), and calcite (Cal2). Veins of Q4 and Cal2 clearly crosscut those of Q3. Calcite in this stage typically occurs in planar and colloform forms. Overall, Stages II and III constitute the principal ore-forming stages at Yingqian.

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