You probably already know this, but if you're new there, you'll find a lot of new friends about 20 minutes up the hill in the San Gabriel mountains. There's Gold in the east fork river at the Heaton Flats campground. Go up Hwy. 39, make a right at the east fork turn-off bridge, then make the left to the east fork. Go over the Cattle Creek bridge and park at the parking lot (go early on the weekends for a spot). The Heaton Flats campground is a short walk (no cars down there). Watch the you tube videos under East Fork San Gabriel river Gold. You'll meet my buddies like Robert Ferguson, Larry Englehart, Daniel (nick name Savage), Odd Ryan, and some old timers that live there and prospect everyday.
The Rangers will say "No Gold panning, no prospecting, no mining, etc." But they are NOT enforcing there own rules. They are waiting for their 'Monument' status with the $$$ to enforce the laws. Go now and enjoy, because the Liberal environmentalist whackos in charge of California would love to have all Gold panners arrested & charged with some kind of environmental hate crime. In Yosemite Natl. Park, panning & detecting is a federal crime. They call it 'Stealing Park Resources'