Mineraldle
Puzzle #35 was chamosite.
Chamosite is the Fe2+ end member of the chlorite group. A hydrous aluminium silicate of iron, which is produced in an environment of low-to-moderate-grade metamorphosed iron deposits, as grey or black crystals in oolitic iron ore. Like other chlorites, it is a product of the hydrothermal alteration of pyroxenes, amphiboles and biotite in igneous rock.
What the record says
Puzzle 35 ran on 19 Aug 2026 and the answer was chamosite, played with 6 guesses against 4 columns. On the record: Crystal system - monoclinic; Strunz group - silicates; Elements - Al, Fe, H, Mg, O, Si; Named after - place.
Beyond the grid the record adds Formula - (Fe²⁺,Mg,Al,Fe³⁺)₆(Si,Al)₄O₁₀(OH,O)₈; Mohs hardness - 3; Named after - Chamoson.
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
- monoclinic
- Strunz group
- silicates
- Elements
- Al, Fe, H, Mg, O, Si
- Named after
- place
Also on the record
- Formula
- (Fe²⁺,Mg,Al,Fe³⁺)₆(Si,Al)₄O₁₀(OH,O)₈
- Mohs hardness
- 3
- Named after
- Chamoson