Discovery	1735 Brandt
Abundance	25
Radius	1.7
Electronegativity	1.88
Ionization	7.881
Number of isotopes	14
Electronic configuration	[Ar] 3d7 4s2
Oxidation states	-1,1,2,3,4,5
Electron by energy level	2,8,15,2

Minerals containing this element : 95

Mineral	Hardness	Density	Formula
	2.00 / 2.50	3.37	NiSeO₃Â·2H₂O
	5.00 / 6.00	7.11	(Fe,Ni)₂P
	5.00 / 5.00	6.17	CoAsS
			FeCrP
	3.00 / 3.00	2.33	CoSO₄Â·4H₂O
			Cu₂MgAsO₄(OH)₃
	6.00 / 6.00		Mn⁴⁺(O,OH)₂Â·(Co,Ni,Mg,Ca)_x(OH)_2xÂ·nH₂O
	2.00 / 2.00	1.90	CoSO₄Â·7H₂O
	2.00 / 2.50	2.10	CuSO₄Â·7H₂O
	4.00 / 4.00		Co²⁺Co³⁺₂Se₄
		2.81	Bi₆(Mg,Co)₁₁Fe₁₄(AsO₄)₁₈O₁₂(OH)₄Â·86H₂O
	3.00 / 3.00	2.93	Co₂(H₂O)₄(AsO₃OH)₂Â·H₂O
	3.50 / 3.50	5.03	PbFe³⁺₂(AsO₄)₂(OH)₂
	4.50 / 5.50	4.50	CuCo₂S₄
	4.50 / 4.50	4.80	CoS₂
	4.50 / 5.00	7.46	CoAs₂
	3.50 / 4.00	3.22	CoFe³⁺₂(AsO₄)₂(OH)₂Â·4H₂O
	4.50 / 4.50	4.00	CaCoAsO₄(OH)
	5.50 / 5.50	6.33	CoAsS
	2.00 / 3.00	3.28	CoSO₄Â·H₂O
	2.00 / 3.00	3.44	Co(AsO₃OH)Â·H₂O
	4.50 / 4.50		CaCo₂(AsO₄)₂Â·2H₂O
	4.50 / 4.50	5.81	Bi₂Fe³⁺(Co,Fe³⁺)(AsO₄)₂(O,OH)₄
	2.50 / 2.50	2.35	Na₂Co(SO₄)₂Â·4H₂O
			NaCo₄(SO₄)(OH)₆ClÂ·6H₂O
	2.00 / 2.50	3.39	CoSe⁴⁺O₃Â·2H₂O
	4.00 / 5.00	5.22	Co₉S₈
	4.50 / 4.50	5.31	PbCo₂(AsO₄)₂Â·2H₂O
	5.00 / 5.50	4.30	Co(UO₂)₂(SO₄)O₂Â·3.5H₂O
	7.00 / 7.00	5.22	CoCr₂O₄
	5.50 / 6.00	7.20	Fe₃C
	2.00 / 2.00	3.05	Ni₄Co³⁺₂CO₃(OH)₁₂Â·3H₂O
	6.00 / 6.00	6.89	CoSbS
	1.50 / 2.00	3.06	Co₃(AsO₄)₂Â·8H₂O
	6.00 / 6.50		FeAs₃
	5.00 / 5.00	4.00	CuNi₂S₄
	2.50 / 3.00	7.00	CoSe
	3.00 / 3.00		Cu₃NiCl₂(OH)₆
	5.00 / 5.00	5.90	Co_0.5Fe_0.5AsS
	1.50 / 2.00	2.80	Zn₆SO₄(OH)₁₀Â·5H₂O
	6.00 / 6.00	7.22	CoSe₂
	3.00 / 5.00	4.13	Co³⁺O(OH)
	2.00 / 3.00	3.30	(Ni,Co)Cu₄(AsO₄)₂(AsO₃OH)₂Â·9H₂O
		5.45	CoS
		2.67	Ni²⁺_1-xCo³⁺_x(OH)_2-x(SO₄)_xÂ·nH₂O where [x=1/3; n=(1-x)]
	6.00 / 6.50	7.10	NiAsSe
		1.65	Na₂Co(SCN)₄Â·8H₂O
			Co₃(V₂O₇)(OH)₂Â·2H₂O
	5.00 / 5.50	7.20	CoSb₃
	4.00 / 4.00	3.97	CuCoCO₃(OH)₂
	4.50 / 4.50	4.50	PbMn³⁺₂(VO₄)₂(OH)₂
	6.00 / 6.50	8.17	CoAs
	3.00 / 3.00	3.71	Cu₃CoCl₂(OH)₆
	4.50 / 5.50	4.80	Co₃S₄
	2.50 / 2.50	2.43	Ca₂MgV⁵⁺₁₀O₂₈Â·16H₂O
	3.00 / 3.00	3.37	Zn₃V₂O₇(OH)₂Â·2H₂O
	5.50 / 5.50	8.00	CoTe₂
	8.00 / 8.50	7.88	(Ni,Fe)₄P
	2.00 / 2.50	3.20	Co(UO₂)₂(AsO₄)₂Â·8H₂O
	4.00 / 4.00	8.00	CoAs
	2.50 / 2.50	1.97	CoSO₄Â·6H₂O
	4.50 / 4.50	5.81	Bi₂Fe³⁺(Fe³⁺,Co)₂(AsO₄)₂(O,OH)₄
	6.00 / 6.50	5.24	NiCr₂O₄
	4.50 / 4.50	4.45	CaNi₂(AsO₄)₂Â·2H₂O
	4.00 / 4.50	5.23	BiNi₂(AsO₄)₂(OH)Â·H₂O
	5.50 / 6.00	6.50	NiAs_3-x
	5.00 / 5.50	7.92	CoSbAs
	3.00 / 3.50	3.67	Co(UO₂)₂(SiO₃OH)₂Â·6H₂O
	1.00 / 2.00		NiBi³⁺OAsO₄
	2.00 / 2.00	2.71	Co₃(PO₄)₂Â·8H₂O
	7.00 / 7.00	6.90	CoSbS
	2.50 / 3.00	6.58	NiSe₂
	1.50 / 2.50	4.90	(Ni,Co)₃₀(As₂O₇)₁₅
		3.31	CoCu₄(AsO₄)₂(AsO₃OH)₂Â·9H₂O
	4.50 / 4.50		PbCo₂(AsO₄)₂Â·2H₂O
	3.50 / 3.50	3.69	Ca₂Co(AsO₄)₂Â·2H₂O
	3.50 / 4.00	3.71	Ca₂Co(AsO₄)₂Â·2H₂O
	4.00 / 5.00	6.90	CoAs₂
	4.00 / 4.50	5.28	BiCo₂(AsO₄)₂(OH)Â·H₂O
	5.00 / 5.50	4.50	CoNi₂S₄
	5.50 / 6.00	6.10	CoAs_3-x
	2.00 / 2.00		Co₃Fe³⁺₂(AsO₄)₄Â·11H₂O
	3.00 / 4.00	4.21	CoCO₃
		4.49	La₃Mn²⁺₃Cu²⁺(Mn³⁺,Fe³⁺,Mn⁴⁺)₂₆(Si₂O₇)₆O₃₀
	2.00 / 3.00		Cu(Fe,Ni)₈S₈
	1.50 / 2.00	2.52	NaCo₄(SO₄)(OH)₆ClÂ·6H₂O
	7.00 / 7.00	7.00	CoSe₂
	3.50 / 3.50	6.00	(Co,Cu,Ni)₃Se₄
	4.50 / 4.50	4.52	CuS₂
	4.50 / 5.00	6.20	Ni₄AsS₂
	5.00 / 5.00	8.00	CoFe
	3.00 / 4.00	3.52	Ca₂Mg(AsO₄)₂Â·2H₂O
	5.50 / 6.00	8.00	FeAs
	5.50 / 5.50	6.76	CoSbS
	1.50 / 2.00	1.87	CoAl₂(SO₄)₄Â·22H₂O