The surface growth micromorphology of some sulfide minerals in hydrothermal deposit s has been
observed by means of STM and SEM at nano2scale resolution. For comparison , the surface st ructures of a set
of artificial pyrite and galena crystals have also been studied. It was discovered that on the surface of some
natural pyrite pisolitic hillock micromorphology was developed , which shows a natural 32dimensional nuclea2
tion. In addition , on the crystal surface of both natural and artificial minerals , funnel2shaped crystals and
pustular2shaped (cellular) growth hillocks were observed. The level and smooth growth steps on the artificial
pyrite surface imply a static crystallization environment , without disturbance and nearly in equilibrium. At
the same time , a great number of pustular2shaped st ructures and st retched pustular2shaped growth hillocks
developed on the crystal surface of hydrothermal sulfide minerals indicate the high super2saturation of the ore2
formation system. The present study reveals that mineral crystallization during the hydrothermal ore2forma2
tion characteristically evolved in three stages : (1) 32dimensional nucleation , (2) step growth , and (3) equilib2
rium polyhedron ; correspondingly the surface micromorphology evolved f rom pisolitic hillock , to pustular and
finally to the growth steps with smooth surface. Therefore , the mineral surface microst ructures formed in
complex geological environment s bear rich information on the thermodynamic and dynamic conditions of the
ore2formation.