Single crystals of BaZnFe6O11 (Zn Y) were grown by the flux technique. Chemical analysis showed the presence of some ferrous ions in most batches. A relation between the Curie temperature and the ferrous content could be established. The anisotropy in the specific resistivity was measured (20–260 Ω·cm in the basal plane, 240–1400 Ω·cm in the c direction) and was found to be a structural effect. The magnetostriction in the basal plane was measured to be 1.5×10−6. The crystal anisotropy field in the basal plane was found to be smaller than 1 Oe at room temperature for all samples and 10–20 Oe at 77°K. Linewidths of thin disks were found to be 14–20 Oe at room temperature and 50–60 Oe at 77°K. The permeability of single‐crystal toroids in the basal plane was measured at room temperatures between 0.5 and 500 MHz. Two dispersion mechanisms were found near 10 and 100 MHz, which could be ascribed to wall and spin relaxation, respectively. The rotational permeability was found to be about 300, whereas from the anisotropy data at least 1300 would have been expected. This discrepancy could be understood from the investigation of the Bloch‐wall pattern of these samples, as will be discussed in some detail.