To put in perspective just how massive Carey's 35-carat engagement ring is, Kim Kardashian's much talked-about Lorraine Schwartz cushion-cut diamond ring from husband Kanye West is 15 carats -- less than half of what Carey's is. Carey also beat out Beyonce's 18-carat Lorraine Schwartz diamond ring from husband Jay Z, valued at over $5 million, as well as Kate Middleton's 18-carat heirloom ring from Prince William.
Rosado, a close friend of Carey's, tells Vogue that the gorgeous ring is "the most challenging piece of jewelry [he's] ever designed."
"I took the standards super high, and I wanted to create a ring that could not be measured up to," Rosado says. "I wanted to create the most gorgeous ring for my dear friend, but I also wanted to create the most stunning ring for one of the most iconic divas of our generation."
The design and construction of Carey's ring took two weeks, with those involved working 12-hour days. An "army of craftsmen," including measurement specialists and a diamond expert, were needed to create the one-of-a-kind piece.
See Mariah Carey's massively gorgeous 35-Carat engagement ring from James Packer
NEW YORK, NY - FEBRUARY 12: Singer Mariah Carey and Nick Cannon attend MTV First: Mariah Carey's 'You're Mine (Eternal)' music video world premiere at MTV Studios on February 12, 2014 in New York City. (Photo by Larry Busacca/Getty Images)
LOS ANGELES, CA - JANUARY 18: Mariah Carey and Nick Cannon (R) arrive at the 20th Annual Screen Actors Guild Awards at the Shrine Auditorium on January 18, 2014 in Los Angeles, California. (Photo by Dan MacMedan/WireImage)
NEW YORK, NY - AUGUST 05: Nick Cannon (L) and Mariah Carey attend Lee Daniels' 'The Butler' New York premiere, hosted by TWC, DeLeon Tequila and Samsung Galaxy on August 5, 2013 in New York City. (Photo by Kevin Mazur/Getty Images for Samsung)
HOLLYWOOD, CA - NOVEMBER 17: TeenNick Chairman and HALO Awards host Nick Cannon and singer Mariah Carey attend Nickelodeon's 2012 TeenNick HALO Awards at Hollywood Palladium on November 17, 2012 in Hollywood, California. The show premieres on Monday, November 19th, 8:00p.m. (ET) on Nick at Nite. (Photo by Charley Gallay/Getty Images For Nickelodeon)
NEW YORK, NY - DECEMBER 15: Mariah Carey leaves the Beacon Theater on December 15, 2014 in New York City. (Photo by James Devaney/GC Images)
LOS ANGELES, CA - MARCH 14: Mariah Carey (L) and actor Jussie Smollett attend the Human Rights Campaign Los Angeles Gala 2015 at JW Marriott Los Angeles at L.A. LIVE on March 14, 2015 in Los Angeles, California. (Photo by Jason Kempin/Getty Images for Human Rights Campaign)
NEW YORK, NY - DECEMBER 03: Mariah Carey performs at the 82nd Annual Rockefeller Christmas Tree Lighting Ceremony at Rockefeller Center on December 3, 2014 in New York City. (Photo by James Devaney/WireImage)
NEW YORK, NY - DECEMBER 03: Singer Mariah Carey performs at the 82nd Annual Rockefeller Center Christmas Tree Lighting on December 3, 2014 in New York City. (Photo by Paul Zimmerman/WireImage)
SHANGHAI, CHINA - OCTOBER 19: (CHINA OUT) Singer Mariah Carey performs live during her 2014 China Tour on October 19, 2014 in Shanghai, China. (Photo by ChinaFotoPress/ChinaFotoPress via Getty Images)
NEW YORK NY - AUGUST 26: Mariah Carey sighting on August 26, 2014 in New York City. (Photo by Josiah Kamau/BuzzFoto/FilmMagic)
HOLLYWOOD, CA - JULY 23: Singer Mariah Carey and actor Dwayne Johnson attend the after party for the premiere of Paramount Pictures' 'Hercules' at the Roosevelt Hotel on July 23, 2014 in Hollywood, California. (Photo by Alberto E. Rodriguez/WireImage)
CAP D'ANTIBES, FRANCE - JUNE 17: (EXCLUSIVE COVERAGE) Mariah Carey performs during Clear Channel Media And Entertainment And MediaLink Dinner at Hotel du Cap-Eden-Roc on June 17, 2014 in Cap d'Antibes, France. (Photo by Tony Barson/Getty Images for Clear Channel)
NEW YORK, NY - JUNE 09: Singer Mariah Carey announces the launch of her Go N'Syde bottle 'Butterfly' at the Saint Regis Hotel on June 9, 2014 in New York City. (Photo by Andrew H. Walker/Getty Images)
NEW YORK, NY - MAY 29: Singer Mariah Carey attends the 2014 Fresh Air Fund Honoring Our American Hero at Pier Sixty at Chelsea Piers on May 29, 2014 in New York City. (Photo by Monica Schipper/FilmMagic)
Mariah Carey performs during the World Music Awards at Monte Carlo Sporting Club, on May 27, 2014 in Monaco. AFP PHOTO / VALERY HACHE (Photo credit should read VALERY HACHE/AFP/Getty Images)
TODAY -- Pictured: Mariah Carey appears on NBC News' 'Today' show -- (Photo by: Peter Kramer/NBC/NBC NewsWire via Getty Images)
LOS ANGELES, CA - MAY 06: (EXCLUSIVE COVERAGE) Singer Mariah Carey attends Mishka B's Epic Bat Mitzvah at 1OAK on May 6, 2016 in Los Angeles, California. (Photo by Jeff Kravitz/FilmMagic)
LOS ANGELES, CA - MAY 06: (EXCLUSIVE COVERAGE) Stella Bulochnikov (L) and Mariah Carey attend Mishka B's Epic Bat Mitzvah at 1OAK on May 6, 2016 in Los Angeles, California. (Photo by Jeff Kravitz/FilmMagic)
Discover More Like This
BACK TO SLIDE
"She obviously has a strong point of view about what she likes," Rosado says of the "Heartbreaker" singer. "We have the same taste, and when it came down to it, I really wanted to create something for her that was about new beginnings. I wanted to give her something super sophisticated and something that took away all of the embellishments that a lot of people use when they design engagement rings these days.
"But it is epic," he stresses. "It's an epic ring for an epic time in her life."
As for Packer's involvement in the design, Rosado says he consulted with the groom-to-be three times during the entire process. The designer also reveals Packer's romantic side, sharing that he left a small empty space on the backside of the band because the businessman wanted to eventually engrave a special sentiment to Carey.
"He wanted to create something very rare and very beautiful around this diamond he chose, and I followed his lead," Rosado says.
The upcoming nuptials will mark the third marriage for both. Carey was first married to music executive Tommy Mottola, and later tied the knot with actor Nick Cannon, with whom she shares 4-year-old twins, Monroe and Moroccan. Meanwhile, Packer has been married twice before as well -- first to model Jodhi Meares, then to model and singer Erica Baxter, with whom he has three children.