Rocksday

Rocksday #2 · October 23, 2026

The answer was Granite

A coarse-grained rock that cooled slowly deep underground, made of quartz, feldspar and mica or hornblende.

Granite — the Rocksday #2 puzzle photo
The photo from that day's puzzle, via Wikimedia Commons — credits

The clues

Type
Igneous rock
Color & luster
Pink, Gray, White, Black · Granular, sparkly
Mohs hardness
6–7
Texture
Coarse-grained (phaneritic)
Found in
Sierra Nevada, California; Stone Mountain, Georgia

How to recognize granite

  • Speckled with interlocking grains you can see without a lens.
  • Glassy gray quartz plus pink or white blocky feldspar.
  • Black specks of mica or hornblende.
  • Hard, with no layering or banding.

Did you know? Most Olympic curling stones are made of granite from Ailsa Craig, a tiny island off Scotland.

Easy to confuse with

Full Granite guidePlay #2Today's puzzle