[6] The mineral occurs in cavities in sedimentary iron and manganese deposits in association with arsenoclasite, shigaite, hematite, hausmannite, triploidite, barite, and manganoan ferroan calcite.
[3] Based on a 1977 experiment that produced triploidite, it is likely that gatehouseite formed by a reaction between hausmannite and basic phosphorus-rich fluids at low temperature and variable pH conditions.
Very small, unidentified pale brownish orange crystals were seen in one specimen; study showed they had a formula of the type M5(XO4)2(OH)4 and contained manganese, phosphorus, and a minor quantity of arsenic.
[6] Gathehouseite was named for Bryan Michael Kenneth Cummings Gatehouse for his contributions to the study of oxides and oxysalts.
[1][6] Due to the small size and intergrowth of the crystals, single-crystal X-ray crystallography is difficult to perform on gatehouseite.