Shiny, silver gray mica thick specimens - photo is representative of the one you will receive - each 5 " long. Mica is a mineral name given to a group of minerals that are physically and chemically similar.  They are all silicate minerals, known as sheet silicates because they form in distinct layers.  Micas are fairly light and relatively soft, and the sheets and flakes of mica are flexible. Mica is heat-resistant and does not conduct electricity. Used in products like cosmetics and filler in cement and asphalt, giving them a shiny look.