Ammonium Iron Cyanide
- Dyes & colorants
- CAS 25869-00-5
- IUPAC: Ferrate(4-), hexakis(cyano-C)-, ammonium iron(3+) (1:1:1), (OC-6-11)
Ammonium Iron Cyanide (CAS 25869-00-5) appears in 1 of the 1,812 car-care products CarCareTruth tracks (as of June 2026).
Ammonium iron cyanide (Prussian blue complex, CAS 25869-00-5) is not classified as a sensitizer, carcinogen, or reproductive toxicant. SARA 313 reportable (threshold 1.0%). At use concentrations in anti-seize paste bound in a grease carrier, dermal and inhalation exposure during normal application is minimal. Not a toxicologically concerning ingredient under normal use conditions.
Ammonium iron cyanide (CAS 25869-00-5) is an inorganic pigment compound belonging to the Prussian blue / Berlin blue family of iron-cyanide complexes. It is the ingredient responsible for the distinctive blue color in Never-Seez Blue Moly and similar blue-tinted anti-seize products. The blue coloration provides a functional benefit: it allows the applicator to visually confirm uniform coverage on fastener threads during application.
The compound is not the active anti-seize agent - that role belongs to the nickel and molybdenum disulfide components. At 5-10% concentration in the paste, it functions purely as a colorant and visual-confirmation aid.
Prussian blue complexes of this type are among the most stable iron-cyanide compounds and do not readily release free cyanide under typical storage or use conditions. The compound is SARA Section 313 reportable at a 1.0% threshold, reflecting its status as a regulated substance even at low concentrations in industrial formulations.
Health & environment profile
- VOC
- no
- Prop 65 listed
- no
- Asthmagen
- no
- EPA Safer Choice
- no
- Aquatic toxicity
- no
- Biodegradable
- no
- Bioaccumulative
- no
- Persistent
- no
- Ozone depleting
- no
- Microplastic
- no
- PFAS
- no
- Env. score
- 5/5
Common questions about Ammonium Iron Cyanide
- What is Ammonium Iron Cyanide used for in car care?
- Blue pigment (Prussian blue / Berlin blue complex) in anti-seize compounds; provides the characteristic blue color that enables visual inspection of coverage during application
- Is Ammonium Iron Cyanide a VOC?
- No. Ammonium Iron Cyanide is not classified as a volatile organic compound (VOC).
- Is Ammonium Iron Cyanide on California's Proposition 65 list?
- No. Ammonium Iron Cyanide is not on California's Proposition 65 list.
1 product contain this
Prop 65
Related
Health and environment notes translate the manufacturer Safety Data Sheet, the GHS classification, and authoritative regulatory listings (California Prop 65, EPA). Not medical advice. They describe the ingredient itself; whether a hazard applies to a finished product depends on its concentration and how it's used.