When heated to 700 °C, indium(III) oxide forms In2O, (called indium(I) oxide or indium suboxide), at 2000 °C it decomposes.
wˌɛn hˈiːɾᵻd tə sˈɛvənhˈʌndɹɪd dᵻɡɹˈiːz sˈiː, ˈɪndiəm ɹˌoʊmən θɹˈiː ˈɑːksaɪd fˈɔːɹmz ɪn tˈuː ˈoʊ, kˈɔːld ˈɪndiəm aɪ ˈɑːksaɪd ɔːɹ ˈɪndiəm sʌbˈɑːksaɪd, æt tˈuː θˈaʊzənd dᵻɡɹˈiːz sˈiː ɪt dˌiːkəmpˈoʊzᵻz.