The microstructure of Zr-Ti-Ni-Cu-X (X=Ag,Al) ingots or melt-spun ribbons was investigated. The ingots were analyzed using a scanning electron microscope with an X-ray energy-dispersive spectroscopy system, and the alloy composition was modified to increase the amount of eutectic on expense of primary crystals. High-resolution electron microscopy observation of thin foils from ribbons of a composition near the eutectic show only extremely small ordered aggregates, while ribbons from alloys near the NiTiCu compound contain nanocrystallites. The addition of silver into Zr-Ti-Ni-Cu alloys results in precipitation of spherical silver crystallites in slowly cooled and melt-spun ribbons. However, their presence has no effect on the alloy's glass forming ability, as they do not serve as nucleation sites for other phases.