The gadolinium garnet system {Gd
zY
3-2x-zCa
2x} [Fe
2-yIn
y] (Fe
3-xV
x)O
12was investigated as a function of x, y, and z for

, and

. The relationships between their compositions and magnetic properties were clarified. It was shown that some combinations of components in this system displayed improvements with respect to temperature stability (

%/°C

C) and ferromagnetic resonance linewidth (ΔH = 20 ∼ 30 Oe) as compared with conventional garnets.