Corrected entry: When Nick and Rachel board the flight from New York and are sitting in their 1st Class pod, they are sitting talking before take off and Rachel has painted nails, but when they arrive in Singapore she does not.
Corrected entry: At the cookery class where the family are making dumplings, Eleanor shows off her emerald ring. Later when Nick proposes on the plane, it is not the same ring. This time it is a tourmaline and not the emerald.
Correction: No one said it is the same ring. Most viewers assume the two rings are one and the same. It is possible they are similar, although different rings.
Not only do people assume they are the same, that is the point of the scene. Eleanor giving Nick the ring shows that she accepts the marriage.
It's the same ring. They are shot from a different angle and with different lighting. The ring actually belongs to Michelle Yeoh in real life...so I'm sure they didn't "use a different ring" by accident. All the jewelry was real in the film. It's what the director wanted. The borrowed pieces from exclusive shops even had bodyguards accompanying them and were off camera when they shot scenes outside or around crowds.
Correction: It is definitely supposed to be the same ring. Remember, the grandma didn't approve and wouldn't give Nick's dad the family ring. Eleanor is finally giving Nick her blessing. Plus, end shot at the engagement party, the mom does not have said ring. It's definitely meant to be her ring.
Correction: A nonstop flight from New York City to Singapore is roughly 18 hours. Sounds like more than enough time for Rachel to remove her nail polish.
jshy7979
It seems highly unlikely someone would remove their nail polish on a flight, but anything is possible.
I don't think nail polish remover is approved to take onto an airplane as it is very flammable.
According to the TSA website, nail polish remover is allowed on board, as long as it meets the size requirements: https://www.tsa.gov/travel/security-screening/whatcanibring/items/nail-polish-remover.
jshy7979