I'm Just going to go with Iowa.
I would ID that as "black sand" type pottery.
From late in the early woodland period to early in the middle woodland.
Leaning towards middle woodland.
They mixed several methods of decorating the exteriors ..like cord marks,incised lines and dashes along with punctuating.
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Yes I found it in central Iowa. Thanks for the info! I'm excited to go back out and look for more pieces!
I have found a point and a couple blades there but don't know what kind they are.