Hello,My name isCustomerand I would love to help.Give me a moment to research for you.
This dinnerware was made by Hermann Ohme of Silesia, the most popular shape being Old Ivory (see photo).
This porcelain was made from 1882 to 1930. A service for 12 would have a value of $1100.00 retail.
They had patterns that were added to their different shapes, Empire Shape, Clarion Shape, Alice Shape, for example.
Go here and you might find the pieces that you have. http://www.replacements.com/china/ohm.htm
If you are looking for pieces to add to this set, then once you find the pattern, look up Hermann Ohme **pattern in Google and you will be given a list of pieces that would be for sale on different sites.
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