What age is the spiral pattern black pottery jar

Spiral pattern black pottery jar is the Warring States period. According to the query related public information, spiral pattern black pottery jar is an ancient Chinese traditional ceramic craft, produced in the Warring States period, more than two thousand years ago. Spiral pattern is a kind of pattern of black pottery, usually made of pottery wheel, rotating and engraving spiral pattern on the surface of pottery, and then applying black glaze for firing.