The altitude is 1,195 m. The main part of the No.3
pegmatite ore vein is from west to north, and the inclination is from south to
west, with unique form, in straw hat shape. The height and width of the hat are
250 m; the diameter of the marginal ridge is 2 km, 20 - 40 m thick. With
concentric ring banded structure, the bell-shaped body part is classified as 9
belts in turn from outside to inside.
The No. 3 mine pit is about 250 m long, 240 m wide and
140 m deep, and it is the mining pit left by the exploration of the No. 3 ore
vein. The mining pit has 13-floor annular ore hauling lane, great and
momentous, like the huge "bullring" in Ancient Rome.