A new preferential etch has been developed which is free of chromium oxide. It is based on various combinations of nitric acid, hydrofluoric acid, and acetic acid. The optimum composition for an etch to reveal haze of all haze-forming metals (Co, Ni, Cu, Rh, Pd) can be determined from a given equation. With the aid of this equation the proportion of acetic acid is calculated as a function of the preselected proportion of nitric acid to hydrofluoric acid. For the first time haze due to nickel can be distinguished from haze due to copper by etching the sample with solutions of different composition. The new etch is highly sensitive to impurity metals precipitated at the surfaces of silicon samples (haze, shallow etch pits) but it reveals also all other lattice defects (slips, dislocations, epitaxial and oxidation-induced stacking faults). The etch works independently of the water orientation.