When my great-grandmother died her jewellery was laid out on a cushion and female relatives, I think in order of closeness of familial ties (daughters, granddaughters, great-granddaughters, nieces/great-nieces etc) were each able to choose one item - I was quite young and have no idea what happened to the bulk of her 'estate'...my sister chose a small cameo pendant and I had a brooch with a stone missing, because although it was costume jewellery with no monetary value I thought my great-grandmother probably wore it a lot (I still have it).
My nan left little of value and therefore her will was simple. My uncle (her only son & her executor) and his wife wanted nothing, same for my mother (her only daughter). I have a couple of boxes of her favourite ornaments, a couple of brass vases and her vinyl records. If my mum, sister or brother wanted anything I'd happily pass it over/share. My uncle had house clearance firm in for everything else. During nan's lifetime I had her engagement ring and a watch in my possession but my nan had always told my sister she'd get her jewellery as they would play dress-up together...Although I have written a will, I didn't see why my sister should have to wait for me to die to get these 2 pieces, so gave them to her, as nan wanted. She did have at least one other ring (with a fairly large stone) and we don't know what happened to her wedding ring either - we suspect 'carers' stole them (as they stole other items, including food and the fish from nan's pond!) Lots of posts have good suggestions to make things fairer - it is such a shame families end up divided over unfair distribution or the dreaded 'vultures' - even when, like me, you have little or nothing of monetary value it is important to discuss your wishes with nearest & dearest and to write a will - can avoid potential family fall-outs while they are also grieving.
@BoadiceaJones, my condolences, and I hope you find a way to sort this out to everyone's satisfaction and that you have something treasured from your mum's possessions/estate to go with your memories.