Another Liliths ring question

So Lilith decided she wanted to be mortal. Her immortality goes into the ring and it’s white and when Lucifer wears it the stone becomes black. I understand this to mean he has his own immortality (when he isn’t self actualizing vulnerability) and it doesn’t need to work.

When he goes to get Chloe out of heaven the ring is swirly until Chloe puts it on, it becomes white, my guess is because it’s working and Chloe wakes back up on earth. This is what I gathered from all that. What is nagging at me is Chloe dying with Rory while wearing the ring and it’s white.

I was nearly certain that I understood the ring until that scene. Anyone care to explain?.