Classification turns on principal use: articles designed and sold primarily for display or decoration — figurines, purely decorative vases, ceramic sculptures — belong under 6913, while items intended for use at the table or in the kitchen classify under the tableware heading even if they are attractively designed. Dual-use articles are classified by their predominant character.

Yes, the two subheadings (691310 for porcelain/china and 691390 for other ceramics) carry separate tariff lines that may have different normal trade relations rates. Additionally, Section 301 additional duties apply based on country of origin rather than material, so both the subheading and the origin must be confirmed before calculating landed cost.