To add:
It has a shiny gold surface, which the picture doesnt really show. It has numerous points and jagged edges and is much heavier than another rock of the same size found in the same yard. I am pretty sure its not gold (99.9999%) but am interested to know for sure. This is not the first time something like this has been found in our substations. Thanks again.
I'm thinking iron pyrite, but I'm no pro ;-) I don't see any oxidation which would usually be seen with exposed iron but who knows. Better quality and close-up photos would help tho.
Also, if the host rock is limestone, that may be yellow/brown calcite. Check the hardness with a penny and see which one gets scratched.
Thanks for the replies. After reading your posts I looked up pictures for iron pyrite and its pretty much identical. Ill put it on the shelf with the collection of shell fossils I have found in our yards. Thanks again!
Wait!!! Don't just take our word for it. Take it to a rock shop, college geology dept., museum, jeweler and just ask. We have seen a bunch, but as I get older, I realize I ain't that smart...
You can buy a gold testing kit for under 10$ amazon.com rub the metal on the paper and put solution on it if it turns the right color its gold. Helps to have the kit if your getting jewelry on your hunts.