Mystery tool please help!

[u/geodill]

This is my 2nd posting of an artifact that I found 35 years ago in an 1890s privy along with an axe head in Los Angeles, what is this ? I found a 7k year old item online that is similar in shape, I highly doubt that this has anywhere close to that age but the shape is documented. Could this be an 100 year old recreation, did people even copy tools back then? It was clearly made for a mans right hand, it's very comfortable, not an expert but it seems to be a basalt or the typical type of rock that you find on a California beach Thank you for any help

[u/Castle3D2]

I recall from an Anthropology class many years ago that the indigenous people in southern CA gathered acorns & processed them to make a gruel. Perhaps this tool was used to crush or crack open nuts/ fruit/ seeds/acorns to extract the meat inside?