Most modern curling rocks come from a very small number of granite quarries, mainly Ailsa Craig in Scotland and the Trefor granite quarry in Wales. Their special granite is unusually tough and resistant to chipping, which is crucial when 40‑pound stones smash into each other on the ice.

Quick Scoop: Where curling rocks come from

1. The two main sources

  • Ailsa Craig, Scotland
    • A tiny volcanic island in the Firth of Clyde, off Scotland’s Ayrshire coast.
* Has unique “Ailsa Craig Common Green” and “Ailsa Craig Blue Hone” granites used for top‑level curling stones.

* Olympic and many elite stones have traditionally been made from this granite.
  • Trefor Granite Quarry, Wales
    • Located at Yr Eifl / Trefor on the north coast of the Llšn Peninsula in Gwynedd, Wales.
* Produces “Blue Trefor” and “Red Trefor” granites used for high‑quality curling stones, including sets supplied to the 2002 Winter Olympics.

* Another major source as quarrying on Ailsa Craig is now tightly restricted because it’s a protected bird sanctuary.

2. Why this granite is so special

  • Curling stones must be extremely hard , dense , and chip‑resistant , or they’d fracture after repeated hits.
  • Ailsa Craig granite has unusual chemistry and tightly bonded minerals that make it exceptionally resistant to chipping and impact damage.
  • The body and “striking band” (the part that takes most collisions) are often made from the tougher common green Ailsa Craig granite, while the running surface can use even finer‑grained material like Blue Hone.

3. From raw rock to curling stone

  • Granite is cut from the quarry, rough‑shaped into a cylinder, then precisely lathed into the familiar 40‑ish pound stone with a concave running surface.
  • The bottom is engineered so it slides on a narrow ring, helping control speed and curl on pebbled ice.
  • After machining, the stone is polished and fitted with a handle on top, then tested for weight, balance, and how it moves on the ice.

4. A bit of history

  • Early curlers in 16th‑century Scotland used whatever river or field stones they could find, with no handles and inconsistent shapes.
  • Over time, as the sport standardized, Ailsa Craig and later Trefor became the preferred sources because their stones performed consistently better and lasted longer.

5. Today’s “trending” context

  • With each Winter Olympics, people rediscover that nearly all Olympic curling rocks trace back to that one Scottish island and that Welsh quarry, which often pops up in news and science explainer pieces.
  • There’s ongoing discussion in curling circles about future sources, since blasting on Ailsa Craig is now limited and demand for stones remains global.

Information gathered from public forums or data available on the internet and portrayed here.