The cheapest stone countertops are usually made of laminate or granite. Laminate is a type of plastic that is glued to a particleboard core and is available in a wide variety of colors and styles. Granite is a natural stone that is quarried in areas all over the world. It comes in a variety of colors, but it can be expensive depending on the quality and thickness you choose.

The cheapest stone countertop is likely to be a laminate. However, it is important to note that the quality and durability of a laminate countertop can vary greatly, so it's important to do your research before making a purchase. Another option would be to consider a granite or marble overlay, which can be a more affordable way to get the look of natural stone without breaking the bank.