Not to be a negative nellie here, but...
there are three things in the description of your stone that tell you it most likely is not a meteorite:
1. "It has a paper thin black crust and grey interior..." While most stony meteorites do have a dark fusion crust and lighter colored interior, the fact that your stone's exterior is black raises a red flag. Only a freshly fallen meteorite has a black fusion crust. Once the stone is exposed to the elements for any length of time, its exterior quickly oxidizes to a dark reddish brown color. A freshly fallen meteorite would have been immediately preceded by a fireball, sonic booms, etc. The chances of finding a fresh meteorite without eyewitness accounts and/or doppler radar data to guide you to it are next to zero. The black crust on your stone is most likely a manganese oxide coating.
2. "...my magnet won't stick to it." While there are stony meteorites that aren't attracted to a magnet, they are exceedingly rare. This alone tells you that it most likely is not a meteorite.
3. "There are sparkles inside the rock." Stony meteorites don't have crystalline components large enough to see without magnification and therefore never sparkle. Sparkly stones are definite meteorwrongs.