During the colonial period, smelting ore in the colonies was illegal, so mine operators at New-Gate had to ship ore to England. After the prison closed in 1827, the Phoenix Mining Company and the Connecticut Copper Company tried to revive production, believing that fewer legal restrictions and new technology would make mining more profitable than it had been in colonial times. Both companies reported good-quality ore, but found processing it for market difficult. The Phoenix Mining Company constructed smelters in the 1830s after the prison closed, yet the ventures were financially unsuccessful and the mines were abandoned again.