This looks like it could be a 5 stone graduated diamond ring in 18ct yellow gold, perhaps an Evans heirloom.
Each stone can symbolise something different to the couple, such as love, devotion, family, friendship, or trust, but mainly they will represent important or special elements of the relationship.
If it is a piece that was passed down, then it will have a rich history, intermingled with love stories from the past, which makes it an even more unique ring.
I would estimate something like this could have a value of £40k-£50k.
Read the full article here: https://www.hellomagazine.com/brides/488868/nicole-scherzinger-confirms-engagement-thom-evans/