Facts
- Chemical formula
- CaSr(Mn³⁺₂Al)[Si₂O₇][SiO₄]O(OH)
- Crystal system
- Monoclinic
- Number of elements
- 7
- IMA status
- Renamed
- Type locality
- Wessels mine
- Named after
- Samuel Milbourn Tweddill
Sources: Wikidata (CC0), IMA list of minerals via Wikidata · Wikidata Q3844522