Help with identification

Hi,
I’m new to this site, so I hope I’m doing this correctly. I found a couple of items on the farm that I need help in identifying. First one is about 10 inches long , one side is perfectly flat so maybe a grinder? Thank you for your help!!

 

Not bad 4 a newbie.......... so FYI....

where's the farm....
is it your farm?
when did u find such things
were they near a structure
can you post bigger pics of other views of the 3....

do u have a tribal nation near you....
or a 1st nations museum in your area...

Help us.....to help you !!!!!

 

Just making them bigger, so everybody can see.

 

Thank you for your response. I live in Petaluma Ca. and I find a lot of Coastal Miwok tribe artifacts in this area. But I haven’t been able to find anything on what the black half circle item is and the arrowhead is nothing like the others in shape and the clarity of the obsidian I’ve found in the past, so maybe it was traded, if so from where? Thank you again-

 

Hello Rosa. You will probably need to find an archeologist familiar with objects from your local area. You might try contacting the Department of Anthropology at the U Of C Berkeley and, in particular, their Archaeology Laboratory:

https://anthropology.berkeley.edu/

https://anthropology.berkeley.edu/california-archaeology-laboratory

 

Thank you, I have a couple of books on the Miwoks, but many of my findings don’t match anything in the book or on the internet. I also contacted Sonoma State University but I never heard back. I will contact U of B tomorrow. Again I appreciate everyone trying to help.