CBP generally looks for a certificate of authenticity from the artist or a recognized authority, an invoice describing the medium and the artist's name, and — for high-value works — appraisal documentation. For works by living artists, a signed statement from the artist confirming hand execution is often sufficient. Reproductions, even high-quality hand-touched ones, do not qualify and are classified elsewhere.

Yes. The US is a signatory to the 1970 UNESCO Convention on cultural property, and bilateral agreements restrict the import of certain categories of cultural objects from specific countries. Importers should confirm that the exporting country has not designated the work as protected cultural patrimony and that any required export certificate from the source country is in order before shipment.