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SHEET /m/francium · PubChem CID 6328145 · CAS 7440-73-5 · REV 2026.07

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Francium

from source

Fr · 223.01973 g/mol

eka-cesium · catium · eka-caesium · Element-Fr

What is Francium?

The rarest naturally occurring element after astatine: at most a few tens of grams exist in the entire earth's crust at any moment. Element 87. from source

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Fig. 1 · 2D structure RDKit

SMILES[Fr]

Where you'll find it

A pure element or an engineered material, rather than an ingredient in a product. See the rest of the element & material group.

Sources & methodology

PubChem CID
6328145
Wikidata
Q671
Structure
PubChem → RDKit
Data refreshed

How MoleculeFinder sources and labels its data