Chalk is a fine-textured form of limestone. It is composed of several tiny fragments of the calcite shells or skeletons of ...

It seems like every other day we hear about some hacker, tinkerer, maker, coder or one of the many other Do-It-Yourself engineer types getting their hands into a complex field once reserved to only a ...

Most natural diamonds have ages between 1 billion and 3.5 billion years. Diamond is the only gem with a single element. Do ...

A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. The ratio of each element is ...