The present disclosure provides a metal compound. The metal compound is represented by a formula (I): Cu2AαB2-αO4-&bgr; (I). A contains at least one element selected from the groups 6 and 8 of the periodic table. B contains at least one element selected from the group 13 of the periodic table, 0<α<2, and 0<&bgr;<1.5. Polymer article containing the metal compound and method for preparing the polymer article as well as selective metallization of a surface of the polymer article are also provided. In addition, the present disclosure provides an ink composition and the selective metallization for a surface of the insulative substrate using the ink composition.