The contrast between the dull grey of the “raw” rock, the bright whites and orangish minerals and the flash from the mica makes for a fascinating display of color and texture.  

Rock Type: Unknown with high mica content

I am not sure what type of rock this is, but it has a lot of mica throughout.  Mica forms in thin individual sheets that easily flake off.  Mica is very reflective and is often the mineral responsible for bright flashes of light when looking at rocks.  It is a silicate mineral and is common in a wide variety of rocks.

Chemical composition:  There are many different types of mica.  Muscovite is the most common light colored mica and has a chemical formula of KAl2(AlSi3O10)(OH)2