Imperfection
im·per·fec·tion | ˌim-pər-ˈfek-shən
noun
A general term used to refer to internal or external characteristics of a gemstone (i.e.: inclusion, fracture, etc.)
Gemstones are formed in a variety of different conditions, which means they are rarely perfect. Imperfections are any of a number of different naturally occurring characteristics of a gemstone, including inclusions or fractures. External flaws that might be found in a gemstone include blemishes, small chips, or scratches, while internal flaws may include fractures, or other crystal and mineral deposits as inclusions that formed millions of years ago when the gem was formed. These imperfections make each gemstone unique, but the fewer there are, the higher the grade the gemstone has and generally the higher its value.