In present work the results of measurements of segregation coefficient of Nd3+ ions in LiLuxY1-xF4 (x=0- 1) crystals are presented. Two methods for Nd3+ ions concentration measurements in the crystals are used. The first one - X-ray fluorescence analysis (XRFA) - is used to establish the absolute concentration of impurity ions, and the second - optical absorption spectroscopy (OAS) - allows to estimate not absolute, but relative impurity concentration. By comparison of the results given by both methods the integral cross-sections of 4I9/2-2G7/2 transitions of Nd3+ ions doped in these crystals were estimated. Thus, the standard samples, allowing to establish the absolute Nd3+ ions concentration in LiLuxY 1-x F4(x=0- 1) crystals by means of OAS-method, were created.© (2010) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.