Lindsay Lohan's engagement ring is so damn powerful it got her parents to share the same air without a single call to police. 

Lindsay showed off the huge rock -- looks to be an emerald in a diamond setting -- while hanging with Michael and Dina Lohan in Brooklyn at Tuesday's Duran Duran concert. Her fiancé, Egor Tarabasov was there as well ... conspicuously behind LiLo and her parents.

TMZ broke the story ... Lindsay got engaged over the weekend to the 22-year-old Russian heir after 5 months of dating.

Lindsay got onstage briefly -- she's featured on DD's "Danceophobia" -- and shouted out her sister Ali Lohan ... who's trying to start her own singing career. She might wanna rub that ring 3 times and make a wish. 

#Romancingthestone