Facts
- Chemical formula
- (Na,Ce)(Y,REE)(HCO₃)(OH)₃·4H₂O
- Crystal system
- Monoclinic
- Number of elements
- 6
- IMA status
- Approved
- Type locality
- Poudrette quarry
- Named after
- Thomas H. Clark
Sources: Wikidata (CC0), IMA list of minerals via Wikidata · Wikidata Q7795558