There is provided an iridium tip including a pyramid structure having one {100} crystal plane as one of a plurality of pyramid surfaces in a sharpened apex portion of a single crystal with orientation. The iridium tip is applied to a gas field ion source or an electron source. The gas field ion source and/or the electron source is applied to a focused ion beam apparatus, an electron microscope, an electron beam applied analysis apparatus, an ion-electron multi-beam apparatus, a scanning probe microscope or a mask repair apparatus.