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Those are Chinese "double gourd" vases in what is known as ""Famille Noire" because of the black grounding. Large ornamental pieces in this style surged in popularity as export-ware to the West from the late 19th Century and into the early decades of the 20th Century. Quality pieces were very pricey and If those were from that period they could have substantial value... but the crucial question is: "are they marked?"
More likely, they will be later post-war copies with a value derived from their decorative appeal rather than as collectibles. Quality period pieces will be marked on the base. Without marks or only with generic marks, they're more likely in the 'decorative copy' category and could be quite recent. There was no formal trade between mainland China and the US after the Chinese revolution of 1949 and trade didn't fully resume until the bilateral agreement of 1979.