Queen Elizabeth's wedding ring was engraved with a secret message and only 3 people knew what it said

Before their passing Queen and Prince Philip celebrated more than seven decades together as husband and wife.

But they kept one closely guarded secret, according to the Daily Mail.

Just like Meghan's and Kate's, the Queen's wedding ring is made from Welsh gold.

What sets it apart is that it's engraved with a secret message chosen by Philip in 1947 -and even those closest to the monarch don't know what it says.

Royal author Ingrid Seward writes in her new book Prince Philip: A Portrait of the Duke of Edinburgh that "Philip didn't have the expense of a wedding ring, as the people of Wales supplied a nugget of Welsh gold from which the ring was made".

"She never takes it off and inside the ring is an inscription.

"No one knows what it says, other than the engraver, the Queen and her husband."

Philip also had her engagement ring made from a tiara that belonged to his mother, Princess Alice of Battenberg.

Photo / Getty

Before he proposed, Philip had the tiara taken apart, and the diamonds repurposed to make a ring for his bride-to-be.

He then designed the three-carat solitaire with five smaller diamonds.

The royals married on November 20, 1947 at Westminster Abbey, with more than 200 million people watching the service on TV from around the world and 2000 guests attending.

This article was first published on the NZ Herald and is republished here with permission.