A method of forming a crystal comprises a crystal forming treatment effected by dipping a substrate having a nonnucleation surface having a small nucleation density and a nucleation surface having a larger nucleation density than said nonnucleation surface and an area sufficiently fine to such an extent as to allow only a single nucleus to be formed in a solution containing a monocrystal forming material to thereby allow a monocrystal to grow from only the single nucleus.