Tallulah Willis 'Took the Driver's Seat' to Find and Design Her 'Dream' Vintage Diamond Engagement Ring

Tallulah Willis/Instagram. Inset: Jon Kopaloff/FilmMagic

Tallulah Willis had a big hand in selecting a diamond and designing her engagement ring from fiancé Dillon Buss.

After announcing the exciting news of her engagement to the film director, Willis, 27, shared the story behind her sentimental sparkler. "Still processing / overwhelmed with the love sent to my and my freckled mans — we are so grateful to all that witness our story's unfolding," said the actress, who is the youngest daughter of Demi Moore and Bruce Willis.

She started by finding a gemstone specialist to help track down the perfect stone for her ring. "I found Anup, @crazygemhunter my new forever friend a few months ago while furiously trying to decode the world of diamonds. My fiancé (!!!) is the most understanding precious human noodle and when we began talking about this seriously I told him due to my lowkey (highkey lol) obsessive, perfectionist, micro lens way of viewing special things in my life I knew I had to be in the drivers seat with this one. And of course Dillon understood - because that's Dillon. 😩," Willis explained.

dillon buss/ instagram

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While "the hunt was on," Willis was introduced to "another magical friend," jeweler Karina Noel. They worked together and "scoured the world" for the right diamond. "No stone left unexamined," Wilis said.

Finally, she found the right one. "After much deliberation we decided on this 1910s elongated asscher cut forged in a riverbed," the star said.

tallulah willis/instagram. Inset: Dillon Buss/instagram

"Once we had the stone, Karina and I went to town and after multiple revisions and stressed texts that it needed to feel like it was on a delicaté finger of a resident of Rivendell / Ancient other worldly aliens (Karina — thank you for putting up with my late night FaceTimes and manic sketches 🤦🏼)," Willis continued. "This is the final result! Group effort, so much love, and a lot of patience for a loony toons girl, I am over the moon."

RELATED: Tallulah Willis, Demi Moore and Bruce Willis' Daughter, Reveals She's Engaged to Dillon Buss

Willis celebrated her engagement by sharing sweet photos as Buss got down on one knee and popped the question. "with absolute most certainty," Tallulah captioned her post.

"I can finally call you my fiancé. Love you forever Buuski Lu, you are my best friend," Buss wrote in his post.

The couple was also celebrated by Tallulah's older sisters Scout, 29, and Rumer Willis, 32.

"I'm so buoyed by this JOYOUS LOVE CELEBRATION!!!! HIP HIP HURRAY!!!!! @buuski@dillonbuss today is a blessing because of your love! 5/4/21 💍Welcome the first official WILLIS BROTHER 😭😭😭," Scout wrote next to a picture of all three sisters celebrating.

Rumer wrote: "I love these crazy kids. Congratulations @dillonbuss and @buuski I love you both so immensely and I am so excited for you."