Demi Lovato is a singer, songwriter and actress as well as an activist. She began her career working with Disney. Her breakout came with the film Camp Rock, in which she starred opposite Nick Jonas.

Helen Doyle Gemologist Prestige Pawnbrokers of Channel 4’s Posh Pawn told Express.co.uk: “The ring is a classic single stone ring with a large central emerald cut diamond approx 10ct which is flanked by two trapezium cut diamonds which look approx 3cts each and really compliment the central stone.

“A simple claw setting means focus is not detracted from the diamonds. I would estimate the ring to be in excess of £500,000.”

Ira Weissman founder of The Diamond Pro told also gave their analysis. They Express.co.uk: “Demi Lovato just announced her engagement to actor Max Ehrich. With a stunning helicopter pad of an emerald cut center diamond and the classic pairing with trapezoid sidestones, Demi’s ring looks to make it to the hall of fame of celebrity engagement rings.

“The approximately 5 carat diamond is clearly of the highest quality and could easily fetch over $250,000.”

Twitter users commented on the stone.

One said: “Demi Lovato’s engagement ring. that’s it. that’s the tweet.”

Another wrote: “That ring is bigger and brighter than my future.”

Brooklyn Beckham revealed the engagement earlier this month.

His fiance Nicola is said to be worth around £40m.

The happy couple has been dating for around nine months before Brooklyn asked her to marry him.

Brooklyn posted: “Two weeks ago I asked my soulmate to marry me and she said yes xx I am the luckiest man in the world. I promise to be the best husband and the best daddy one day. I love you baby xx.”