Mineraldle

Puzzle #56 was cummingtonite.

Cummingtonite is a metamorphic amphibole with the chemical composition (Mg,Fe2+)2(Mg,Fe2+)5Si8O22(OH)2, magnesium iron silicate hydroxide.

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From Wikipedia (CC BY-SA 4.0)

What the record says

Puzzle 56 ran on 9 Sep 2026 and the answer was cummingtonite, played with 6 guesses against 4 columns. On the record: Crystal system - monoclinic; Strunz group - silicates; Elements - H, Mg, O, Si; Named after - place.

Beyond the grid the record adds Formula - ☐Mg₂Mg₅Si₈O₂₂(OH)₂; Named after - Cummington.

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
H, Mg, O, Si
Named after
place

Also on the record

Formula
☐Mg₂Mg₅Si₈O₂₂(OH)₂
Named after
Cummington

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