Could this possibly be a meteorite? It strongly attracts a magnet and leaves no streak whatsoever. To me it looks awfully similar to many of the Canyon Diablo pieces from the Barringer crater in Arizona. I found it probably about 80-100 miles from the crater.
looks like you're in Gilbert. Short hop over to ASU & their meteorite lab. Heard they cut way back on doing IDs (budget) but if you walk in with one in your paw someone will tell you.
781 E. Terrace Rd., Tempe, AZ 85287 Phone: (480) 965-6511 Website: http://meteorites.asu.edu/
If I recall right, it's on the second floor