Demi Lovato, 27, announced her engagement to Max Ehrich, 29, on Wednesday with a series of lovely pictures, one of which was a close up of the huge rock on the pop star's ring finger. The emerald-cut diamond with which the actor popped the question is reportedly worth at least $500,000 and might have cost him even more than $850,000.

According to a report in E! News, the ring which has newly adorned the left hand of Demi Lovato features a central diamond that is estimated to be between a whopping seven and 10 carats and could have cost as much as millions, as suggested by four experts. The emerald-cut stone in the centre is further flanked by trapezoid accent diamonds as well.

When I was a little girl, my birth dad always called me his “little partner” - something that might’ve sounded strange without his southern cowboy like accent. To me it made perfect sense. And today that word makes perfect sense again but today I’m officially going to be someone pic.twitter.com/8IboUPjWcC

— Team Demi (@ddlovato) July 23, 2020

Jenny Luker, president of Platinum Guild International USA, told the outlet: "The center diamond looks around 10 carats. Since the diamonds appear to be set in platinum, they sparkle even brighter! I would estimate a ring like this costs approximately $500,000."

Andrew Brown, CEO of WP Diamonds also estimated the diamond to be 10 carats, set with "two-plus carat trapezoids on each side in a Harry Winston style mounting, featuring a double claw on the prongs." He said that a ring of this size would retail close to $1 million, and could go closer to $2.5 to $3 million if it is indeed a piece by Harry Winston.

Meanwhile, Kathryn Money of Brilliant Earth said that the diamond could be between eight and 10 carats while the total weight of the ring could be between 9.5 and 11.5 carats, adding that that the sparkler could have cost upwards of $850,000. "Depending on the quality and specific characteristics of the center gemstone, we estimate the ring's cost is between $450,000 and $850,000," she said.

However, Shannon Delany-Ron, Director of Communications at JamesAllen.com estimated that the center diamond is about seven carats, and said it might have cost the "Young and the Restless" star about $250,000 to $300,000. Delany-Ron also said that there might be a hidden meaning behind the ring's design. She explained: "Three stone rings like Demi's hold a symbolic meaning and represent the past, present and future of a relationship."

Demi Lovato
Demi Lovato attends the Demi Lovato: Simply Complicated YouTube premiere at The Fonda Theatre on 11 October, 2017 Getty

As per Harper's Bazaar, the ring has been designed by Rodeo-based celebrity jeweller Peter Marco. The report stated that the stone looks to be set in platinum, and is flanked by what appear to be two pentagonal-cut stones. The outlet reported that such emerald-cut stones have been spotted on several other celebrity brides, including Beyoncé, Sarah Jessica Parker, Amal Clooney, Grace Kelly, and Jennifer Lopez.