When you attempt to find the value of dishware, make sure you include the pattern in your search. State the company who made it. Then, add a brief description if you don't know the pattern. Note the background color, edge details (like flowers or gold rims), the primary color of decoration, images shown in the pattern like flowers (state what kind of flower), people, landscape, or animals. This will help to establish the pattern.
Swartzburg china is available for a wide variety of prices. Check out Kovels, Replacements, or Ruby Lane for values. If you decide to sell your china, remember that you will not get the stated value if someone else sells it for you.
Older china is not in high demand right now. Older people are downsizing, and younger people do not want the old-fashioned looks of many older patterns, especially the ones that feature flowery images and sentimental motifs.