But there are often straightforward possible reasons why the royals may take off their engagement rings from time to time, such as pregnancy swelling, sporting events or just favouring a different gem for a specific outfit. Diamond expert, Maxwell Stone said: “With the exception of Queen Letizia, who hasn’t been seen with her sophisticated engagement ring since 2012, it’s incredibly rare to see one of the royal ladies without their precious gem.

“A keen sportswoman, Kate Middleton has an active lifestyle, so it’s a shame that she has to remove her gorgeous sapphire to participate in events – though sapphires are an extremely durable gemstone, Kate’s boasts both sentimental and monetary value, so she wouldn’t want to risk damaging it.

“Mike Tindall actually considered this when he designed Zara Tindall’s engagement ring – ensuring that it had a low profile setting so she wouldn’t have to remove it when she competed in sporting events.”

Express.co.uk has collated pictures of when royal women notably stepped out without their stunning engagement rings.