# What type of atom is phosphate?

$\text{Phosphate}$ is not an atom but an ion radical, i.e. $P {O}_{4}^{3 -}$
A phosphate is thus the salt of phosphoric acid, ${H}_{3} P {O}_{4}$. Because phosphates and biphosphates ($H P {O}_{4}^{2 -}$) are generally insoluble, they are present in a lot of metal ores.