I honestly can't tell by the pics here if they are, indeed, artifacts. Going on your word, I'll say they are.( I have no reason to doubt you and pictures never allow cruder pieces to pass as artifacts on the web) with that out of the way, I'd say they are crude hand spades. Seems like I see some wear on the one to the right. My guess, but don't be surprised when you get geofact from other guys here. They mean no bad, it's just that the absolute proof isn't visible.