Sterling is supposed to be 92.5% silver. It's been my experience that it ranges anywhere from 89-92% pure....most of it running around 91%. Refiners get their cut & will only pay 90% of melt. Once you do the calculations(spotx.9x.9) you can see that when you are selling to a refiner sterling is worth about 81% of spot.
My records show the first set of candlesticks posted will scrap out at just under 2 troy oz of sterling. There's a profit there, but not as big as you would first think when you factor in the $10 shipping.
The Duchin candlesticks in that size scrap out at less than 1/2 ounce each. The bottom line is you have to know what each item scraps out at & what the refiner will pay before you buy. In general, on ebay there are buyers that either don't know what they are buying or they are willing to pay spot without taking into account that it has to be refined & that the refiner gets their cut.