Found rock with purplish/ blue glass or crystal looking insides.

[history hunter]

I was MDing in a park and found these rocks. It looked like rock on the outside and the purple glass on the inside. There was a lot of it in each hole I dug.

 

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[norbyx]

They look nice,wonder what they could be.

 

[garrettJL]

looks like iron slag from a furnace. Used to find lots of that stuff around years ago. Huge historical site nearby that was an old iron furnace.

 

[GoGoGopher]

Maybe Purple quarts, or even amethyst, depending on where it was found...Nice!

HH,

 

[baspinall]

yep

looks like iron slag from a furnace. Used to find lots of that stuff around years ago. Huge historical site nearby that was an old iron furnace.

 

[mcb66]

Yep slag glass from a furnace. Although I once found some like this where a church had burned. It was the remnants of a stained glass window.