It can be created by a substance that is foreign to the chemical composition of the stone, by an internal crystal that was not fully formed, or by a small fracture within the stone. Many gemstones have inclusions that are characteristic to that stone and help in identifying it. For diamonds, their clarity is graded on a scale from Flawless to Included. All grading is carried out under 10X magnification. No internal or external inclusions can be seen.
Inclusions are difficult to see by untrained individuals.
Inclusions are clearly visible with magnification. When found under magnification, inclusions can often be seen later without the aid of magnification. In severe cases, inclusions may affect the durability of the stone. F These stones appear colorless against a white background. G, H, I Stones of less than half a carat will look colorless, while other stones might look colorless to the untrained eye though they contain slight traces of color.