This is the first thing I found that I thought, Why isn’t that a tool? Well over ten years ago now, I thought it was broke at first, tried to fit it together with another piece found next to it but they never quite lined up.
Some people will agree, some will say natural. The problem is there is no definitive way to prove it is or isn't a tool since it doesn't look like a typical scraper, knife, blade, or point.
I would say it's not a tool since there are no markings that prove it was altered. You could disagree and state your reasons and the never ending circle begins.
You can spend the time trying to force "non-traditional looking items" into the tool category or spend that time searching for items with that aren't questionable in the least.
Art??, you mean the fake stuff on ebay call "Indian art".... I find it hard to believe that is art, Indian artifacts are very well made, what you have is not....