ðə haɪdɹˈeɪɾᵻd fˈɔːɹm kæn biː pɹɪpˈɛɹd baɪ dˌiːkəmpˈoʊzɪŋ pɹɪsˈɪpᵻtˌeɪɾᵻd ænd "ˈeɪdʒd" ɡˈæliəm haɪdɹˈɑːksaɪd æt fˈaɪvhˈʌndɹɪd dᵻɡɹˈiːz sˈiː.
The hydrated form can be prepared by decomposing precipitated and "aged" gallium hydroxide at 500 °C.