Manganese is an element, not a rock. It can be found in a variety of minerals with differing chemical formulae. The chemical symbol for manganese is Mn.
The most important mineral of manganese is pyrolusite - MnO2.
Formula: Mn
The chemical symbol of manganese is Mn.
The manganese(IV) selenide has the chemical formula MnSe2.
Formula: MnSO4
Mn
MnSO4.
MnO2
Manganese(II) chloride (MnCl2). Manganese has multiple valence states.
The chemical formulas of manganese nitrates are Mn(NO3)2 and Mn(NO3)3.
Manganese dioxide is itself a compound with formula = MnO2
MnH2PO4
MnSO4