Mineraldle
Puzzle #70 was ettringite.
Ettringite is a hydrous calcium aluminium sulfate mineral with formula: Ca6Al2(SO4)3(OH)12·26H2O. It is a colorless to yellow mineral crystallizing in the trigonal system. The prismatic crystals are typically colorless, turning white on partial dehydration. It is part of the ettringite-group which includes other sulfates such as thaumasite and bentorite.
What the record says
Puzzle 70 ran on 23 Sep 2026 and the answer was ettringite, played with 6 guesses against 4 columns. On the record: Crystal system - trigonal; Strunz group - sulfates-related; Elements - Al, Ca, H, O, S; Named after - person.
Beyond the grid the record adds Formula - Ca₆Al₂(SO₄)₃(OH)₁₂·26H₂O; Named after - Edouard Candlot, Ettringen.
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
- trigonal
- Strunz group
- sulfates-related
- Elements
- Al, Ca, H, O, S
- Named after
- person
Also on the record
- Formula
- Ca₆Al₂(SO₄)₃(OH)₁₂·26H₂O
- Named after
- Edouard Candlot, Ettringen