I agree with the opinion that it is worked, and it is a very large tool or Blade.
It looks to be made of a light colored Rhyolite (I want to check pictures of local New England lithic samples to see if the light color and spotting is patination or natural cortex color)
I like the term Creek Chatter, but It likely doesn’t apply here. And, it does look like it was made from a large flake.
I like it.