Warm Metalic Rock? (Betcha cant figure this one out!)?

Question

Ok....

I found a few rocks a couple years ago....

When I found them they were on top[ of a pile of dirt and there was a couple inches of snow in the ground....the snow where the rocks were had melted....and when i picked them up they were warm to the touch

They are a metalic blue in color (but I have since found red and purple ones as well)

Anybody have any sorta idea what kind of rock they are?

Answer 1

Sounds like slag. Any smelting furnaces near where you found them?

However, it is virtually impossible to ID anything without seeing it.