China, Tang Dynasty, "Kaiyuan Tongbao" Bronze Cash Coin

The Kaiyuan Tongbao (开元通宝) was the standard copper coin introduced in 621 CE during the reign of Emperor Gaozu, founder of the Tang dynasty. Its name, meaning “Circulating Treasure of the Kaiyuan Era,” marked the beginning of a unified, enduring monetary system after centuries of fragmented coinage.

What made it most significant was its wide influence—the Kaiyuan Tongbao became the model for East Asian coinage in Japan, Korea, and Vietnam for centuries. The value of these coins would also become standardized by the government, whereas previously the value of cash coins was assigned based on weight. Starting in the Ming dynasty, Kaiyuan Tongbao coins would also become one of the most important types of cash coins to be used in traditional Chinese medicine, due to a belief that the materials used in the coins and the green patina that developed over time could be used to cure certain diseases.

The Tang dynasty (618–907 CE) itself was a golden age of Chinese civilization, known for its cosmopolitan capital at Chang’an, thriving Silk Road trade, flourishing arts, and openness to foreign cultures and religions.

Each coin comes with a Certificate of Authenticity.