Ultramarine blue

Ultramarine blue is a deep blue pigment, historically ground from lapis lazuli and now made synthetically. Its listing in the United States is narrow: it is permitted for colouring salt intended for animal feed, not for human food.

Where it is and isn’t permitted

Status of Ultramarine blue by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationPermitted21 CFR 73.50retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFANot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.

What it is made from

Manufactured by heating china clay, sodium carbonate and sulfur to form a sodium aluminosilicate with sulfur trapped in the crystal lattice, which is what produces the colour.

  • Vegan
  • Vegetarian
InChIKey
IRERQBUNZFJFGC-UHFFFAOYSA-L
PubChem
CID 71587188

Every name it appears under

15 recorded names. A label may use any of them.

CAS registry number

  • 57455-37-5

As it appears in regulation

  • Ultramarine blue

Other names

  • 3516 ULTRA BLUE
  • 3522 ULTRA BLUE
  • ALUMINUM SODIUM THIOSILICATE BLUE
  • Azure blue
  • IRERQBUNZFJFGC-UHFFFAOYSA-L
  • Lazurite
  • LAZURITE (CA2NA6(AL6(SIO4)6(SO4)S))
  • LAZURITE (NA5(AL3(SIO4)3S))
  • Ultramarine
  • ULTRAMARINE (MINERAL)
  • Ultramarine Blue
  • ULTRAMARINE BLUE (MINERAL)
  • ULTRAMARINE BLUE CI 77007

Hazard reference values

No reference value for this substance in the sources we hold.

Evidence and how bodies read it

Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.

Sources for this page

  • ecfr retrieved 2026-09-07

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable:/api/v1/additives/ultramarine-blue.json