It depends on the age of the thimble, if it is very old 200 years you might get a few hundred dollars for the thimble as long as it is in immaculate condition. The rarer the thimble the more valuable.
Depending on brand name/designer, age (antique? ), condition, and attractiveness, a bone china thimble could be worth anywhere from one to twenty dollars. If it is a specialty/collector's item or a Wedgewood thimble, it could be worth more.