Provenance

Reference data from EU CLP Annex VI and published regulations — verify against your supplier's SDS before use.

Build a label

Substance profile

Cobalt

Cobalt is a gray metal, hexagonal or cubic and is odorless.

CAS 7440-48-4 Danger

Cobalt Safety Data Sheet →

01 · Identification

What Cobalt is

Cobalt is a gray metal, hexagonal or cubic and is odorless. It boils at 2927 °C, melts at 1495 °C, is soluble in water.

Under the GHS it carries the signal word Danger. It is classed as hazardous Air Pollutants (HAPs).

CAS number7440-48-4
EC number231-158-0
Index number027-001-00-9
Chemical class Hazardous Air Pollutants (HAPs)

Other names for Cobalt

  • Aco 4
  • Aquacat
  • C.I. 77320
  • Co 0138E
  • Cobalt Element
  • Cobalt Fulleride (Coc20)
  • Cobalt Metal Dust
  • Cobalt Metal Fume
  • Cobalt-59
  • Super Cobalt

02 · GHS classification

Hazards and label elements

Harmonised classification under CLP Annex VI. This is the legally binding classification in the EU; other jurisdictions may differ.

Signal wordDanger
Hazard statements assigned to Cobalt
CodeHazard statement
H350 May cause cancer <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H341 Suspected of causing genetic defects <state route of exposure if it is conclusively proven that no other routes of exposure cause the hazard>.
H360F May damage fertility.
H334 May cause allergy or asthma symptoms or breathing difficulties if inhaled.
H317 May cause an allergic skin reaction.
H413 May cause long lasting harmful effects to aquatic life.

Precautionary statements: P201, P261, P272, P273, P280, P308, P313, P333, P501

03 · Physical and chemical properties

Cobalt properties

Every value is shown with the conditions it was measured under and the source it came from. Where sources disagree, all values are listed rather than one being picked — the difference is usually a different form of the substance, not an error.

Property Value Conditions Source
Boiling point 2927 °C (5300.6 °F) HSDB
3100 °C (5612 °F) NIOSH
2870 °C (5198 °F) at 760 mmHg CAMEO
Melting point 1495 °C (2723 °F) HSDB
1493 °C (2719 °F) NIOSH
Density 8.92 g/cm³ NIOSH
8.9 g/cm³ at 20 °C HSDB
Solubility Soluble in dilute acids HSDB
Readily soluble in dilute nitric acid HSDB
Insoluble NIOSH
Vapor pressure 0 mmHg approx NIOSH
0 mmHg at 20 °C CAMEO
Lower explosive limit (LEL) Noncombustible Solid in bulk form, but finely divided dust will burn at high temperatures. NIOSH

Values compiled from PubChem Laboratory Chemical Safety Summary. Temperatures converted to Fahrenheit for reference.

04 · Handling and storage

Storing and handling Cobalt

Storage conditions

Keep container tightly closed in a dry and well-ventilated place. Air sensitive. Handle and store under inert gas.

Source: Hazardous Substances Data Bank (HSDB)

Incompatible materials

Incompatible materials: Oxidizing agents, mineral acids, acetylene, hydrazinium nitrate. Material readily reacts with acids generating flammable and/or explosive hydrogen gas.

Source: Hazardous Substances Data Bank (HSDB)

Reactivity

Pyrophoric COBALT is a reducing agent. Decomposes acetylene in the cold as the metal becomes incandescent [Mellor 14:513(1946-1947]. Incompatible with oxidizing agents such as ammonium nitrate, bromine pentafluoride, and nitryl fluoride.

Source: CAMEO Chemicals

Planning storage for a mix of chemicals? Check Cobalt in the storage compatibility matrix →

Get the free GHS / CLP / OSHA deadline calendar

Verified 2026–2029 compliance dates in one PDF — plus alerts when the rules change.