Clarity refers to how clean the diamond is in regards to its microscopic attributes, both internally (dubbed inclusions) and externally (dubbed blemishes). Inclusions can be other materials or particles that are bonded with the diamond as it forms in the Earth. They are also considered ailments in the structure of the diamond itself, and most commonly found in the form of tiny cracks. Some of the factors that go into characterizing an inclusion include its size, color, location, and visibility.