Provenance

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

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Substance profile

Cobalt sulfide

Cobalt sulfide is a black amorphous powder.

CAS 1317-42-6 Warning

01 · Identification

What Cobalt sulfide is

Cobalt sulfide is a black amorphous powder. It melts at 1117 °C, is practically insoluble in water.

Under the GHS it carries the signal word Warning.

02 · Identifiers

Cobalt sulfide identifiers and molecular data

Cobalt sulfide CAS number and EC number

CAS number1317-42-6
EC number215-273-3
Index number (CLP Annex VI)027-003-00-X

03 · GHS classification

Cobalt sulfide hazard classification

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

Cobalt sulfide pictograms and signal word

Signal wordWarning

Cobalt sulfide hazard class and category

GHS hazard classes Cobalt sulfide falls into
Hazard class Category From code Pictogram
Skin sensitisation GHS chapter 3.4 Category 1 or 1A or 1B H317 GHS07
Hazardous to the aquatic environment - acute GHS chapter 4.1 Category 1 H400 GHS09
Hazardous to the aquatic environment - chronic GHS chapter 4.1 Category 1 H410 GHS09

Where two values are shown with “or”, the hazard statement is shared by more than one category or by more than one class, and the code alone does not say which. H272, for example, belongs to oxidising liquids and to oxidising solids — the physical state decides. The binding answer for a specific entry is in the CLP Annex VI table itself.

Cobalt sulfide hazard statements (H-codes)

Hazard statements assigned to Cobalt sulfide
CodeHazard statement
H317 May cause an allergic skin reaction.
H400 Very toxic to aquatic life.
H410 Very toxic to aquatic life with long lasting effects.

This page lists only the codes assigned to Cobalt sulfide. The full reference lives on the hazard statements hub, the precautionary statements hub and the GHS pictograms hub.

Safety Data Sheet

Getting an SDS for Cobalt sulfide

A Safety Data Sheet is written for a product, not for a substance: the supplier of the grade you actually buy issues it, so two suppliers of Cobalt sulfide issue two different sheets. That is why there is no single authoritative SDS for a substance to download — what there is, is the job of collecting the sheets for the products you hold and keeping them current as suppliers revise them.

04 · Precautionary statements

Cobalt sulfide precautionary statements

CLP Annex VI assigns 8 precautionary statements to Cobalt sulfide. They are grouped the way a label groups them: what to do before handling, what to do when something has already happened, how to store it and how to dispose of it.

Response

What to do once exposure, spillage or fire has already happened.

Disposal

What has to happen to the contents and the empty container.

Reading the notation. is a blank the supplier fills in — not a truncated sentence.· [square brackets] mark a part printed only when it applies.

05 · Names in the regulation

Cobalt sulfide name in 23 EU languages

CLP Annex VI Part 3 is published in every language edition of the regulation, and the identification column is written out in each of them. Nothing below is translated by us: each line is the name as that edition prints it. Under Art. 18(2) the substance name from Annex VI is a lawful product identifier, so this is the wording to put on a label going to that market — and where the cell lists several designations, any one of them qualifies.

Language Name in CLP Annex VI Part 3
Bulgarian български кобалтов сулфид
Spanish español Sulfuro de cobalto
Czech čeština sulfid kobaltnatý
Danish dansk cobaltsulfid
German Deutsch Cobaltsulfid
Estonian eesti koobaltsulfiid
Greek ελληνικά θειούχο κοβάλτιο
English English cobalt sulfide
French français sulfure de cobalt
Croatian hrvatski kobaltov sulfid
Italian italiano solfuro di cobalto
Latvian latviešu kobalta sulfīds
Lithuanian lietuvių kobalto sulfidas
Hungarian magyar kobalt-szulfid
Maltese Malti sulfur tal-kobalt
Dutch Nederlands kobaltsulfide
Polish polski siarczek kobaltu(II)
Portuguese português sulfureto de cobalto
Romanian română sulfură de cobalt
Slovak slovenčina sulfid kobaltnatý
Slovenian slovenščina kobaltov sulfid
Finnish suomi kobolttisulfidi
Swedish svenska koboltsulfid

All 23 language editions of Annex VI carry this entry. Irish is the twenty-fourth official EU language and has no line here for a different reason: no consolidated CLP text has ever been published in Irish, so there is no Irish edition of Annex VI to quote a name from. Source: consolidated CLP, CELEX 02008R1272, language editions. © European Union, https://eur-lex.europa.eu — only the electronic Official Journal of the European Union is authentic.

06 · Label elements

Cobalt sulfide GHS label elements

Everything CLP Annex VI fixes for Cobalt sulfide, laid out the way it appears on a label. The greyed lines are the parts only the supplier can fill in.

GHS07 Exclamation mark pictogramGHS09 Environment pictogram

Warning

Cobalt sulfide

  • May cause an allergic skin reaction.
  • Very toxic to aquatic life.
  • Very toxic to aquatic life with long lasting effects.
  • Avoid breathing dust/fume/gas/mist/vapours/spray.
  • Contaminated work clothing should not be allowed out of the workplace.
  • Avoid release to the environment.
  • Wear protective gloves/protective clothing/eye protection/face protection/hearing protection/
  • Get medical advice/attention.
  • If skin irritation or rash occurs:
  • Collect spillage.
  • Dispose of contents/container to

Supplier name, address and telephone number· Product identifier·Nominal quantity

Need this as an actual label? Open Cobalt sulfide in the GHS label constructor →

07 · Health hazards

Cobalt sulfide health hazards and exposure limits

Cobalt sulfide hazard summary

May cause skin sensitization and asthma after prolonged contact; [ICSC] See Cobalt.

Source: Haz-Map, Information on Hazardous Chemicals and Occupational Diseases

Cobalt sulfide carcinogenicity classification

IARC classification Group 3 — Not classifiable as to its carcinogenicity to humans
IARC monographs Volume 52: (1991) Chlorinated Drinking-water; Chlorination By-products; Some Other Halogenated Compounds; Cobalt and Cobalt Compounds; Volume 131: (2023) Cobalt, Antimony Compounds, and Weapons-grade Tungsten Alloy

... There is limited evidence for the carcinogenicity of cobalt(II) sulfide in experimental animals. ... Overall Evaluation: Cobalt and cobalt compounds are possibly carcinogenic to humans (Group 2B). /Cobalt and cobalt compounds/

Source: Hazardous Substances Data Bank (HSDB)

There is inadequate evidence for the carcinogenicity of cobalt and cobalt compounds in humans. There is sufficient evidence for the carcinogenicity of cobalt metal powder in experimental animals. There is limited evidence for the carcinogenicity of metal alloys containing cobalt, chromium and molybdenum in experimental animals. ... Overall Evaluation: Cobalt and cobalt compounds are possibly carcinogenic to humans (Group 2B). /Cobalt and cobalt compounds/

Source: Hazardous Substances Data Bank (HSDB)

An IARC group and a CLP classification answer different questions. IARC judges whether the evidence for cancer in humans is strong enough; CLP Annex VI is the legally binding EU classification. A substance can carry one and not the other.

08 · Physical and chemical properties

Cobalt sulfide 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.

Cobalt sulfide melting point

Property Value Conditions Source
Melting point 1117 °C (2042.6 °F) HSDB
1116 °C (2040.8 °F) above this value ICSC

Cobalt sulfide density

Property Value Conditions Source
Density 5.45 g/cm³ HSDB
5.5 g/cm³ ICSC

Cobalt sulfide solubility

Property Value Conditions Source
Solubility Insoluble in water HSDB
0.00038 g/100 cc H2O at 18 °C at 18 °C HSDB

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

09 · Source notes

Further notes on Cobalt sulfide

These are descriptions rather than measured values, so they are kept out of the table above and quoted here with the source that reported them.

Solubility

Using OECD Guideline 105 (Water Solubility), the water solubility of cobalt monosulfide at 21 to 23 °C and pH 6 varied with loading concentration and dissolution time. Under the conditions of this test, the dissolution of CoS is 103.7 ug/L for a 28-day endpoint (1 mg/L loading), 11362.4 ug/L for a 7-day endpoint (10 mg/L loading) and 7666.8 ug/L for a 7-day endpoint (100 mg/L loading).

Source: HSDB

10 · Handling and storage

Cobalt sulfide storage and handling

Cobalt sulfide safe storage

Separated from strong oxidants.

Source: ILO-WHO International Chemical Safety Cards (ICSCs)

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

11 · Questions

Cobalt sulfide — frequently asked questions

What is the CAS number of Cobalt sulfide?

The CAS number of Cobalt sulfide is 1317-42-6. Its EC number is 215-273-3.

What does a Cobalt sulfide label have to show?

Under CLP Annex VI the label for Cobalt sulfide carries the pictograms Exclamation mark and Environment and the signal word is Warning.

Is Cobalt sulfide flammable?

CLP Annex VI assigns Cobalt sulfide no flammability hazard class. That is not a statement that it cannot burn: the harmonised list only records the hazards that were assessed for it.

Is Cobalt sulfide a carcinogen?

CLP Annex VI records no harmonised carcinogenicity classification for Cobalt sulfide. Annex VI is a list of agreed classifications, not a list of substances found safe, so this is an absence of a classification rather than a clean bill of health. IARC places it in Group 3: not classifiable as to its carcinogenicity to humans.

What is the melting point of Cobalt sulfide?

The melting point reported for Cobalt sulfide is 1117 °C (2042.6 °F) (HSDB).

Nearby

Substances next to Cobalt sulfide

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