The glasses with the compositions of 22.5RE(2)O(3)-47.5MoO(3)-30B(2)O(3) (RE: Sm, Gd, Tb, and Dy) (mol%) were prepared by a conventional melt quenching method, and the formation and laser patterning of ferroelastic beta'-RE2(MoO4)(3) crystals were examined. The initial crystalline phase was beta'-RE2(MoO4)(3) in all the glasses, and the second crystalline phases were rare-earth borates such as Gd(BO2)(3), Tb(BO2)(3), and DyBO3, and alpha-RE2(MoO4)(3) in the glass with Sm2O3. It was confirmed from polarized optical microscope observations and micro-Raman scattering spectra that beta'-RE2(MoO4)(3) crystal lines having periodic refractive index changes were patterned by irradiations of continuous wave Yb:YVO4 fiber laser (wavelength:1080 nm, power: 0.5-2.0W, scanning speed: 8-20 mu m s(-1)). It was found that the periodic degree of refractive index changes depends on the kind of RE3+ ions. The present study demonstrates that the appearance of periodic domain structures is an intrinsic feature in the laser patterning of ferroelastic beta'-RE2(MoO4)(3) crystals. (C) 2012 Elsevier B.V. All rights reserved.