Section 2: Equipment
2.1 Curling Stones
Curling stones are made of dense, polished granite. The majority of competition stones are crafted from granite quarried on Ailsa Craig, a small volcanic island off the coast of Ayrshire, Scotland. The two granite types — Blue Hone (extremely rare, used for the running band) and Common Green — are prized for their low water absorption and consistent hardness. Some stones are also sourced from Trefor, Wales.
- Weight: Between 17.24 kg and 19.96 kg (38–44 lb), including handle and bolt (Rule C1(a)).
- Circumference: Maximum 91.44 cm (36 in).
- Height: Minimum 11.43 cm (4.5 in).
- Running band: A narrow, concave annular ring on the bottom of the stone — the only part that contacts the ice. The concavity reduces friction and allows the stone to curl.
- Handle: A gooseneck handle bolted to the top, used to impart rotation (turn) during delivery. Handles are colour-coded to distinguish the two teams (typically red and yellow).
Each team uses 8 stones per game (16 total on the sheet). Stones must not be altered, heated, or treated to change their playing characteristics.
2.2 Brooms and Brushes
- Purpose: Sweeping the ice surface ahead of a moving stone to influence its speed and trajectory.
- Construction: Modern brooms use a carbon fibre or fibreglass shaft with a fabric pad head. Traditional corn brooms are rarely used in competition.
- WCF Approval: All broom heads must comply with WCF specifications. Directional fabric, waterproof coatings, or any material that deposits debris on the ice is prohibited.
- Stabiliser broom: The delivering player uses a broom or stabiliser (delivery stick) in the non-throwing hand for balance during the slide.
2.3 Footwear
- Slider shoe: Worn on the sliding foot (left foot for right-handed deliverers). The sole is coated with Teflon or a similar low-friction material to allow a smooth glide during delivery.
- Gripper shoe: Worn on the hack (push-off) foot. The sole features a high-traction rubber coating for grip on ice.
- Slider guards: Removable rubber covers placed over the slider sole when not delivering, to prevent slipping while sweeping or walking.
2.4 Additional Equipment
- Stopwatch: Used by the skip or vice-skip to time stone speed (split times between hog lines) for weight judgement.
- Measuring device: Used by officials to determine which stone is closest to the tee when it cannot be determined visually.
- Eye on the Hog: Electronic sensor embedded in the stone handle that detects whether the stone was released before the hog line. A green light indicates a valid release; a red light indicates a violation.