Unsure

[UNIQUE MINDSET1221]

Okay I bought a Small Steel statue of a chicken at a garage sale didn't think much of it until I got home.i went to set it on the table when I heard movement inside of it. It was pretty heavy so i didn't think it would be hollow but sure enough i take a better look at it and it looks like someone had made a while underneath it and welded it closed as it was two different colors now. I grabbed a metal grinder and very carefully made an opening and to my surprise found what appeared to look like dark brown sand and these two pieces of the same material but we're shaped like pebbles soft not much weight. I have searched everywhere online but haven't found one thing explaining what this could be so please if anyone has any insight in this it would be greatly appreciated.

 

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