Holly Madison

Holly Madison isn’t exactly an average girl, so it only makes sense that her engagement ring is quite the spectacle.

“My fiancé designed it himself,” Madison told People of the Alan Friedman sparkler, “because I told him that’s what would make it most special.”

What makes it so unique? First off, it’s huge — Friedman surrounded the 18-carat, cushion-cut yellow diamond with pink and yellow diamond flowers. Oh, and it also has special “hidden touches” that are special to the couple.

“Because we love owls, there is a hidden owl engraved on the rose gold in between two of the flowers,” the former Girls Next Door star told People. “The band is art nouveau–inspired, to go with the flowers.”

Love it!

Madison’s ring is one of the more unusual celebrity engagement rings we’ve heard about, but plenty of stars are stepping away from the ordinary — and into some seriously distinctive engagement rings.

Kate Middleton

Kate Middleton engagement ring

The engagement ring Prince William gave to Kate Middleton in late 2010 has a special place in his heart: It’s the same 18-carat sapphire-and-diamond ring that once belonged to his mother, Princess Diana.

“This was my way of making sure that my mother didn’t miss out on today,” William told reporters of why he opted for the heirloom ring.

Jennifer Aniston

Jennifer Aniston engagement ring

Justin Theroux really loves Jennifer Aniston — and he showed it by dropping at least $500,000 on her yellow diamond engagement ring in 2012. Aniston hasn’t talked at length about the huge sparkler, but we know one thing for sure: It’s worth more than most people’s homes.

“If this is a fine-quality diamond of at least 10 carats, which it looks to be from initial photos, we could be talking about a million-dollar ring here,” Anthony Sarkissian of Premier Jewelry Lenders in Beverly Hills told SheKnows at the time.

“Keep in mind that 10-carat-and-over diamonds command a premium price in the diamond industry, because they are just more rare than smaller diamonds,” Sarkissian added. “The ring looks to be a cushion-cut or oval-shape diamond, mounted in a classic halo design. It may have Micro-Pave diamonds around the center stone as well.”

Angelina Jolie

Angelina Jolie engagement ring

Brad Pitt was pretty hands-on when it came to designing the engagement ring for the mother of his six children, Angelina Jolie.

“Brad had a specific vision for this ring, which he realized over a yearlong collaboration,” jeweler Robert Procop told The Hollywood Reporter of the oblong-shaped diamond ring. “He wanted every aspect of it to be perfect, so I was able to locate a diamond of the finest quality and cut it to an exact custom size and shape to suit Angelina’s hand… The side diamonds are specially cut to encircle her finger. Each diamond is of the highest gem quality.”

The estimated cost? At least $250K.

More celebrity wedding style

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Photos: Getty, Daniel Tanner/WENN.com