I would appreciate some opinions , iron slag ??

[PikesPeakCharlie]

A friend found this in the South Platte river in Denver , I have not been able to put a magnet to it yet. the top sure looks like cooled molten metal ,it is heavy .

 

[Old Pueblo]

Looks like it to me.

 

[50bmg]

that looks torch cut to me

 

[4x4x4]

....Knocked off the lip of a smelter bucket ?

 

[PikesPeakCharlie]

I was trying to figure out the smooth slightly curved side , knocked off of the lip of a smelter bucket/crucibal makes a lot of sense. Thanks for the replies

 

[50bmg]

could also be a chunk of a bucket from a bucket dredge.
any mining in the area?

 

[Icewing]

Are you for sure it's metal?
The edges look like they could be broken stone.