Sure, the diameter is 10” on every plate. 5 plates in total.

Thanks, Yoel,
Vintage and antique porcelain is not bringing very much money on the auction market today; these are about $6-10 per plate, with collectors looking for larger sets rather than small numbers as you have here. It's a bit confusing as you may see these advertised on websites such as Replacements, so it's important to keep in mind that those values are retail whereas the values Mearto gives are for auction only.
Based on the photographs and information provided, and subject to examination, you have:
A set of five painted and parcel gilt porcelain service plates
Old Abbey by Limoges, France, retailed at Stern Brothers, New York City, mid 20th Century
10 inches diameter
PROVENANCE: owned by client's grandmother
$30-50*
*represents a fair-market value for auction purposes; retail or asking price may vary.

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