Gadolinium scandium gallium garnet doped with chromium and magnesium GSGG:Mg:Cr4+ is a material for passive Q-switching in 1 µm region. The valence state of chromium ion Cr4+ is provided by use of charge compensator. The GSGG : Cr4+ (Gadolinium scandium gallium garnet) crystals are grown by Zchochralski method in argon-oxigen atmosphere. Crystals of GSSS:Mg:Cr4+ possessing the contrast parameter close to the one of YAG:Cr4+ crystal passive Q-switch have some advantages: possibility to provide necessary initial transmission at less thickness, transparency in the visible range which simplifies the alignment procedure.