High‐field magnetic moment measurements have been completed in NixCu1−xalloys1near the critical concentration2(x≃0.44). Fields of 150 kG or higher and temperatures from 4.2 to 1.5 K were employed. The general features of the data are: (1) the differential susceptibility at high field, &khgr;HF, decreases with increasing field and with decreasing temperatures; (2) &khgr;HF increases with increasingxup tox=0.42 and is relatively constant fromx=0.44 to 0.48; (3) linear extrapolation toH=0 yields a moment &sgr;(0) which is linear withxforx≥0.44 corresponding to about 0.6 &mgr;B/added Ni atom; (4) forx<0.44, &sgr;(0) decreases less rapidly down tox=0.32 (the lowest value ofxinvestigated so far). These results are compared with recent low field measurements of Kouvel and Comly3and Robbinset al.4The general features of &khgr;HF and &sgr;(0) are compared with uniform and nonuniform (or clustering) models3,4for occurrence of ferromagnetism in Ni&sngbnd;Cu alloys.