Investigations of magnetic dilution in Y{sub}3Fe{sub}5O{sub}12 (VIG) indicate that magnetic and dielectric parameters suitable for microwave applications can be obtained at cryogenic temperatures. For simultaneous dilutions of 35 into the octahedral (a) sublattice and 27 into the tetrahedral (d) sublattice, there were no apparent degrading effects on the dielectric loss tangents. At low temperatures, a-site substitutions of In caused the expected large increases in saturation magnetization and corresponding decreases in Curie temperatures. Moreover measurements of hysteresis loops showed that coercive fields ～0.5 Oe could be obtained at T < 77 K despite the likely sharp rise in anisotropy. Dilution by In also lowered anisotropy fields by a factor greater than five from that of Y{sub}3(Fe,Al){sub}5O{sub}12 in both {Y,Ca}{sub}3(Fe,V,In){sub}5O{sub}12 and Y{sub}3(Fe,Al,In){sub}5O{sub}12 compounds.
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