Jen sure isn't shy!

Attending the LACMA 2012 Art + Film Gala honoring Ed Ruscha and Stanley Kubrick in Los Angeles, Jennifer Aniston showed off two major assets Oct. 27: her ample cleavage and her massive engagement ring from fiance Justin Theroux.

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Clad in a floor-length black gown as she schmoozed with guests -- including Cameron Diaz and Salma Hayek -- on the arm of Theroux, Aniston risked a nip slip in the daring design.

Inside the bash, held at the Los Angeles County Museum of Art -- the same venue where Angelina Jolie debuted her engagement ring from Aniston's ex Brad Pitt in April -- Aniston put her dazzling diamond from Theroux on display as she chatted with Ellen Barkin and Joan Collins during the event's cocktail hour. "Her ring is huge," an onlooker at the event tells Us Weekly, adding that Aniston's bauble was accented by a bridal-inspired French manicure.

Engaged since August, Aniston, 43, "cried" when her Wanderlust costar, 41, asked for her hand with the $500,000 ring. Speaking for the first time publicly about her engagement during an October interview with pal Chelsea Handler, Aniston wiped away tears as she gushed about Theroux. "I just got verklempt," Aniston told Chelsea Lately host Handler at the time.

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Though details of their impending nuptials are scarce, a source tells Us Weekly Aniston and Theroux would love "destination wedding, kind of like eloping with a few friends. There will be the feeling of a vacation, since that's their favorite thing to do."

This article originally appeared on Jennifer Aniston Flaunts Cleavage, Shows Off Engagement Ring at LACMA Event With Justin Theroux