Lily Collins' engagement ring was designed with a see-through diamond and could be worth $100,000

• Lily Collins recently described her engagement ring as her "favorite new accessory."
• The ring, given to her by her fiancé, director Charlie McDowell, was custom-made by jeweler Irene Neuwirth with a rose-cut diamond.
• According to Apeksha Kothari, the Chief Operating Officer of diamond search engine Rare Carat, the ring likely cost between $75,000 and $100,000.
• Kothari also said that the ring's bezel setting creates a see-through effect across the three or four carat diamond.

Lily Collins' "favorite new accessory" is her one-of-a-kind engagement ring.

On Tuesday, the actress shared a selfie in which she's seen holding up her left hand to show off her jewelry, which features a square diamond set in a yellow-gold band. The ring was custom-made for her by jeweler Irene Neuwirth.

In an email sent to Insider, a representative for Neuwirth described the piece as a "rose-cut diamond engagement ring." According to Apeksha Kothari, the chief operating officer of diamond search engine Rare Carat, a ring like Collins' could have cost between $75,000 and $100,000.

Kothari also said the diamond is likely between three and four carats.

"Rose cuts are a particular kind of antique cut that is much flatter than the traditional brilliant-cut diamond," she said. "As a result, they sparkle a little less as they did in the olden days, but they do look larger face up."

"This one is set in a bezel setting, which lets you see through the diamond to the skin — a unique setting choice," Kothari added.

The engagement ring previously puzzled gemologists, as its nontraditional design resembles a quartz stone, according to Rare Carat founder Ajay Anand. Such a gem would retail for a much lower price — around $5,000.

Collins and her fiancé, director Charlie McDowell, are clearly happy with the design. On Instagram, McDowell thanked Neuwirth for "making the most beautiful ring" he said he's ever seen.

"Thank you from the bottom of my heart SO much for the most stunning, perfect ring. It's breathtaking. ❤️" Collins added.

Neuwirth first replied to McDowell, writing: "thank you for trusting me ♥️." She then sent a similar message to Collins: "oh my goodness. It was my absolute pleasure. The perfect muse. Congratulations ♥️♥️♥️."

McDowell proposed to Collins in Arizona's Sedona desert last week. On Instagram, Collins described being engaged as "the purest joy." She also shared photos of her ring as well as the moment McDowell proposed to her.

"I've been waiting my lifetime for you and I can't wait to spend our lifetime together," she wrote.

• Read more:
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