Mineraldle
Puzzle #23 was strengite.
Strengite is a relatively rare iron phosphate mineral with the formula: FePO4·2H2O. The mineral is named after the German mineralogist Johann August Streng (1830–1897). Lavender, pink or purple in hue, it is similar to variscite and is partially soluble, particularly in conditions where there is a low pH and low oxidation-reduction potential. The color comes from ferric ion (Fe3+).
Read about it on Wikipedia →
What the record says
Puzzle 23 ran on 7 Aug 2026 and the answer was strengite, played with 6 guesses against 4 columns. On the record: Crystal system - orthorhombic; Strunz group - phosphates-related; Elements - Fe, H, O, P. 1 of the 4 columns is blank in the source (Named after), so nobody could score it either way.
Beyond the grid the record adds Formula - FePOâ‚„ * 2Hâ‚‚O.
Mineraldle builds its record from Wikidata - CC0 1.0. The description above comes from the same place the game credits on every reveal: English Wikipedia verbatim extract, CC BY-SA 4.0. The puzzle itself is still playable in the archive, and every answer that has been and gone is listed on the past-answers page.
How it scored
- Crystal system
- orthorhombic
- Strunz group
- phosphates-related
- Elements
- Fe, H, O, P
- Named after
- Not recorded
Also on the record
- Formula
- FePOâ‚„ * 2Hâ‚‚O