Abstract: The present invention relates to quality control methods using inorganic binding peptides, wherein inorganic entities are identified using inorganic-binding peptides specifically binding to the inorganic entity of interest. In particular, the invention includes a method for the identification of defects or inhomogeneities on a surface by detecting an inorganic entity of interest. It further includes a method for the isolation of powder particles comprising an inorganic entity of interest from a mixture of powder particles. In addition, the present invention relates to inorganic-binding peptides comprising the amino acid sequence MTWDPSLASPRS (SEQ ID NO: 31) and the amino acid sequence LNAAVPFTMAGS (SEQ ID NO: 32), respectively.