Mạc dynasty
The Mạc dynasty, which usurped power between the years 1528 to 1592, also minted its own coinage, but they began to use zinc and iron, which were cheaper metals, and they further allowed private coinage to develop which decreased the quality of the coinage. After the Lê dynasty returned to power they tried to combat these monetary practices, but the shortage of copper (as the mines where the copper came dumb were mostly in areas controlled by China) and the division of the country between the two rival lordships (or principalities) of the Trịnh and Nguyễn lords made these measures ineffective.