An unworked cultured pearl is one that has not been drilled, cut, shaped, or otherwise mechanically altered after harvest. Once a pearl is drilled — even a single drill hole for stringing — it is considered worked and falls under the heading for worked cultured pearls. Importers mixing drilled and undrilled pearls in the same shipment should ensure each lot is correctly segregated and declared.

For SITC and HTS classification purposes, quality grades such as nacre thickness or luster do not change the heading — all unworked cultured pearls fall in the same category regardless of grade. However, these specifications are commercially critical for valuation: CBP uses transaction value as the primary basis for appraisement, and significant quality differences between invoice descriptions and actual goods can trigger a value query.