Vale (NYSE:VALE) has halted fresh investment in its Rio Colorado potash mine in Argentina. In a tersely worded press release announcing the move, the company said that "in the current macroeconomic environment, the economics of the project are not in line with Vale's commitment to discipline in capital allocation and value creation."

Rio Colorado is a $5.9 billion project that was anticipated to produce more than 4 million metric tons of potash annually. The substance is a potassium-based fertilizer.

Vale previously halted work on Rio Colorado this past December. As of the end of 2012, the company had invested more than $2.2 billion in the project.