A nickel crucible used for melting an analytical sample in the pretreatment of the analytical sample, characterized in that the purity of the nickel crucible is 99.9999 wt % or higher. Also provided is a method of analysis, comprising melting a sample by the use of the nickel crucible for melting having a purity of 99.9999 wt % or higher, and analyzing the melt to thereby obtain an analytical result in which the respective lower limits of determination of Mn, Al, Si, Mg, Pb, Fe, Co, Ti, Cu, Cr, Zr, Mo, and W are Mn: 5 wtppm, Al: 10 wtppm, Si: 10 wtppm, Mg: 5 wtppm, Pb: 5 wtppm, Fe: 5 wtppm, Co: 5 wtppm, Ti: 20 wtppm, Cu: 20 wtppm, Cr: 10 wtppm, Zr: 5 wtppm, Mo: 2 wtppm, and W:10 wtppm. In light of the recent analytical technology demanded of fast and accurate measurement of high purity materials, high purity analysis is attained through inhibition of mixing of impurities from the crucible.