Any California Gold Token Experts Willing To School Me?

I inherited this token recently. I have tried for days to research these things, but there are so many varieties, manufacturers, and fakes out there that I'm lost. I am fairly confident that it is not a modern replica/fake, as it was either one of my grandfathers, or my fathers. I don't think any of them acquired any coins (except pocket change finds) since the 1970's.
Anyway, I cannot find any photos of this specific token on any reference website. There are a few that are similar, but the features are slightly different.
This token it exactly .400" across the flats in diameter. Someone wrote on the holder that it is $1/4, which I assume is its relative size.
My question is; is there a way to tell if this is an 1800's made token, or a 20th Century reproduction? Is there a way to tell if it is solid gold vs gold plated? If solid, has anyone ever published the alloy of Karat used? Has anyone ever tried to figure out what the approximate weight (if gold) would be for a $1/4 equivalent token. To me, this may be a rabbit hole that may be impossible to decipher, but I figured I'd post it here and see what I can learn.
Thanks in advance