What is Portland Cement?
For starters, Portland cement has nothing to do with a city in Oregon or Maine bearing the same name. The name is derived from Portland Stone, quarried on the Isle of Portland in England. The material has been in widespread use for more than 200 years and is one of the basic ingredients in concrete, mortar, stucco and grout. There are five types of Portland cement, each with its own strengths and weaknesses; some set faster or harder than others or work better in certain applications. The type you find in most home centers is “Type I.”
Don’t “mix up” the words concrete and cement. Concrete contains only about 10% cement; the rest is water (about 20%), aggregate (about 65%) and air (about 5%).
Sometimes a trademarked name is just the best way to describe a product, here are some that have now become acceptable, generic terms.