If you start a collection of Flow Blue, here is a fantastic resource for Flow Blue collectors, you can date your English Flow Blue by the registration numbers on this chart
Here is a video from Martha Stewart about collecting flow blue and its history.
Here are and tips from Estate Sales News with links to appraisal associations. ASEL does not certify appraisers, but does provide contact information for their local member estate liquidators. Expert Estates is a member of both
the American Society of Estate Liquidators and the Certified Appraisers
Guild of America.
There
are several appraisal societies and each one has certain criteria that
members must meet. Some estate sales companies offer appraisal services,
however, that does not make them appraisers. They may be experienced
and knowledgeable, but belonging to one of these associations includes a
code of ethics as well as specific appraisal education.