Mineraldle
Puzzle #83 was forsterite.
Forsterite (Mg2SiO4; commonly abbreviated as Fo; also known as white olivine) is the magnesium-rich end-member of the olivine solid solution series. It is isomorphous with the iron-rich end-member, fayalite. Forsterite crystallizes in the orthorhombic system (space group Pbnm) with cell parameters a 4.75 Ã… (0.475 nm), b 10.20 Ã… (1.020Â nm) and c 5.98 Ã… (0.598Â nm).
Read about it on Wikipedia →
What the record says
Puzzle 83 ran on 6 Oct 2026 and the answer was forsterite, played with 6 guesses against 4 columns. On the record: Crystal system - orthorhombic; Strunz group - silicates; Elements - Mg, O, Si. 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 - Mgâ‚‚SiOâ‚„; Mohs hardness - 7.
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
- silicates
- Elements
- Mg, O, Si
- Named after
- Not recorded
Also on the record
- Formula
- Mgâ‚‚SiOâ‚„
- Mohs hardness
- 7