Old grinding mill?

[Sample Pan Dan]

Found this in our travels in them thar hills NE of San Diego. Couple old mine locations in the area. Thinking this was here before the stamp mills came in?

 

[Sample Pan Dan]

Thanks Lanny.
Can't wait to go again, but between family and that 4 letter word "work" it can be tuff to get out there. Plus gated roads makes it that much harder :-(