Our "Dinosaur Tooth"

Some of you may have noticed this at our house sitting on the mantle.  We unearthed this jem of a tooth while do some landscaping with a backhoe in the front yard.  It's definately not your typical "rock".  The rough upper part looks as if it were part of a jaw bone broken off.  Who knows, if we would've stopped the landscaping maybe we could've had a full blown archealogical dig here at the house.