Vintage sterling silver studs.
My father is a goldsmith and to supplement his jewellery business, would also buy and sell jewellery over 25 years ago. He later ended up giving me loads due to the demand for making engagement and wedding rings grew, he no longer had the time to sell the 'other' jewellery. I've recently been going through the bags and bags of sterling silver studs, cleaning and putting them into backing cards. See them here.