KNbO_3 crystal was grown by Vertical Bridgman method using encapsulated crucible into stoichiometry materials. Initial crystal was K_4Nb_6O_<17> whose composition was Nb-rich and final crystal was K-rich composition. Middle section of as-grown boule, however, was KNbO_3 crystal. This is explained by growth from K-rich solution. Along growth direction KNbO_3 crystal was colored pale red, milk white and blue.
