Mineraldle
Puzzle #42 was coesite.
Coesite is a form (polymorph) of silicon dioxide (SiO2) that is formed when very high pressure (2–3 gigapascals), and moderately high temperature (700 °C, 1,300 °F), are applied to quartz. Coesite was first synthesized by Loring Coes, Jr., a chemist at the Norton Company, in 1953.
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What the record says
Puzzle 42 ran on 26 Aug 2026 and the answer was coesite, played with 6 guesses against 4 columns. On the record: Crystal system - monoclinic; Strunz group - oxides-hydroxides; Elements - O, Si; Named after - person.
Beyond the grid the record adds Formula - SiOâ‚‚; Named after - Loring Coes Jr..
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
- oxides-hydroxides
- Elements
- O, Si
- Named after
- person
Also on the record
- Formula
- SiOâ‚‚
- Named after
- Loring Coes Jr.