Aren’t you lucky she is asking for Jewellery rather than a pair of Gucci Shoes or some expensive Brazilian hair. I consider Jewellery such as Gold and Diamond assets because of their high resale value. The good thing about jewellery, provided it is pure gold or silver, is that they hardly damage and have nearly infinite life. As such you can still sell that and recover a substantial part of your money if not all.
I know someone who acquired so much jewellery she divided them into three sold one and paid for her of about Masters in the UK. That is the beauty with Assets with strong resale value. Imagine if all that where bags or dresses, I doubt if she would salvaged much.
There will off course always exist the danger of being robbed or missing but at least that to an extent is within your control. Splurging on exotic and luxury items is good if you can afford it but PLEASE never do if you cannot afford it. You can afford in this sense means you have the cash to pay for it and by buying it you are not compromising on the basic necessities of life. No point sacrificing for your children’s school fees, or putting three square meal at home, or getting health insurance because you want to splurge on Jewellery.
So, to answer your question go ahead and buy if you can AFFORD IT AND HAVE THE CASH TO PAY FOR IT WITHOUT SACRIFICING BASIC RESPONSIBILITIES.