Winter Olympics 2022 - Why are there lights on the stones in curling? How much do the stones weigh?

ByEurosport

Published 08/02/2022 at 07:48 GMT

Curling has already played a huge part of the opening days of the 2022 Winter Olympics and the lights on the stones have been spotted by virtually all spectators. So what is the purpose of them and what happens if the red lights come on? Read on for the explanation. Watch every moment of Olympic Winter Games Beijing 2022 on discovery+

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Curling has taken centre stage in the opening days at the 2022 Winter Olympics.

Team GB's Bruce Mouat and Jennifer Dodds have been battling hard in the mixed doubles but after a semi-final defeat to Norway, the pair lost the bronze-medal match to Sweden.

But one of the questions that keeps coming up is what are those lights on the stones? Read on to find out!

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WHY ARE THERE LIGHTS ON THE CURLING STONES?

As you will see on the stones there are a pair of red and green lights on either side of the handle. These are a tracking system to ensure that athletes release the stone before the first hog line.

For the non-curling aficionados, the hog line is a red line at both ends where teams have to release the stone before crossing them.

Italy's Stefania Constantini was caught out by this against Team USA in their second match as she was penalised for a hog line violation in the sixth end. It is worth noting that it is rare for the light to turn red at elite level.

A heat sensor is embedded into the ice which is triggered if a hand continues to hold onto the stone handle while crossing the line. Each stone has batteries to power the sensors.

If the hand is not released before crossing the line then the lights turn red and the team will be penalised by having to remove the stone from play.

WHAT ARE THE STONES MADE OF?

The stones are made of a specific type of granite, found on the island of Ailsa Craig in Scotland.

HOW MUCH DO THE STONES WEIGH?

Each curling stone cannot weigh more than 19.96kg and no less thank 17.24kg, including the handle.

The stone also cannot be wider than 91.4cm or be any taller than 11.43cm.

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WHAT IS THE FORMAT FOR THE CURLING IN BEIJING?

There are medals up for grabs in three events: women’s, men’s and mixed doubles. Ten nations compete in each.

The ‘round robin’ stage consists of each team playing every other team once and placing in a table based on matches won. The top four in that table qualify for the semi-finals – the knockout stages.

The winners of the semi-finals play for gold and silver medals while the two losers from the last four play for the bronze medal.

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Watch every moment of Olympic Winter Games Beijing 2022 on discovery+

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