Lily Collins Says Unique Diamond Engagement Ring Is 'Exactly What I Wanted ... He Knew Me So Well'

From his road trip proposal to the unique ring he created in collaboration with jewelry designer Irene Neuwirth, Lily Collins says her fiancé, writer/director Charlie McDowell, totally nailed their engagement!

The actress, 31, made a virtual appearance on Thursday's episode of Live with Kelly and Ryan, where said said she knew McDowell (who is the son of Mary Steenburgen) was the one "the second" they met, but she had no idea when he would pop the question.

"I can’t believe I get to call myself a fiancée now," Collins gushed, telling hosts Kelly Ripa and Ryan Seacrest, "I was very surprised as to when and where it would happen. But it was kind of one of those situations where I knew the second that I met him, that I wanted to be his wife one day."

Live with Kelly and Ryan/YouTube

"It was just a matter of when, really,” she added with laugh. "We were just on a road trip through New Mexico in Sedona for the last week. And it happened in New Mexico."

The Inheritance star was completely surprised by the well-thought-out engagement — which McDowell filmed with a self-timer — and the unique ring he made for her.

Lily Collins/Instagram

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Holding her left hand up to the camera so Ripa and Seacrest could get a better look at the ring (which features a bezel setting and a thin gold band), Collins explained, "It’s a rose-cut diamond. Charlie designed it with Irene[Neuwirth]."

"I was very surprised by it, but it’s exactly what I would’ve wanted and he knew me so well, obviously," she shared.

Ripa, 49, seemingly agreed, telling Collins, "Those diamonds yield the longest marriages" and are "very lucky."

Lily Collins/Instagram Lily Collins and Charlie McDowell

"Ooo," the actress replied, flashing a big smile. "I didn't even know that!"

Last week, the Extremely Wicked, Shockingly Evil and Vile star announced the happy news on Instagram alongside two photos of the cute couple and a close-up of her unique ring.

Lily Collins/Instagram

“I’ve been waiting my lifetime for you and I can’t wait to spend our lifetime together...” Collins captioned the series of photos, which capture intimate moments during and after the proposal.

McDowell also announced their engagement on his own Instagram page, sharing a smiley photo of his new fiancée flashing her ring: “In a time of uncertainty and darkness you have illuminated my life. I will forever cherish my adventure with you. 💍🎉” he captioned the post.

Charlie McDowell/Instagram

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He received a slew of congratulations from his celebrity followers including Beth Behrs, Zachary Levi and Neuwirth, who commented on McDowell's photo with a string of red heart emojis.

The director replied, "Thank you for making the most beautiful ring I've ever seen." Collins chimed in as well adding, "Thank you from the bottom of my heart SO much for the most stunning, perfect ring. It's breathtaking."

Allen Berezovsky/Getty

A representative for Neuwirth confirmed the ring is a "one-of-a-kind rose-cut diamond." The designer thanked McDowell on Instagram for trusting her with the task and called Collins the "perfect muse."

Collins and McDowell first sparked dating rumors in July 2019, when they were spotted on an outing together in Los Angeles, according to Metro UK.

The director was previously romantically linked to Game of Thrones' Emilia Clarke and Girl With the Dragon Tattoo star Rooney Mara.

In February 2019, Collins and To All the Boys I’ve Loved Before star Noah Centineo ignited relationship rumors after being photographed at the Vanity Fair Oscars Party, but sources confirmed to PEOPLE at the time that the two, who share the same manager, are just friends.