I lived and worked in San Diego County for many years so I am quite familiar with the area and the gold locations within the county. Unfortunately for the small-scale or recreational miner, most of the county's gold production was in the form of lode or hard-rock gold, with little recorded placer gold production. Just the same, I am writing this post primarily with you, the San Diego County placer miner, in mind.
The Julian-Banner Gold Belt
The main gold mineralization belt in San Diego County lies in and around the Julian-Banner area. Beginning in 1869 nearly 225,000 ounces of gold were produced from lode mines in this area, much of that gold coming from the Jackson Mine. Hard-rock gold mining continued in the Julian-Banner area sporadically until the late 1950s, when mining activity finally came to a halt.
You can find some placer gold in the small creeks and washes in this area, including the upper reaches of the San Diego River, but be advised most of this area is private property and is probably not open to recreational mining. In the 1980s before the highway department ran us out for safety reasons (fearing our mining activities would undermine the roadbed or we'd get struck by some out-of-control driver), myself and others used to pan, sluice, and highbank the creek (Julian Creek? Banner Creek?) that parallels the Banner Grade Highway just beyond the town of Julian. I pulled two beautiful matching nuggets from this location as well as good fines and flake gold, so it was a disappointment to all of us when we were told we could no longer mine there. (I thought you should know this if you live in San Diego County, just in case you have some sort of "in" or connection in Julian.)
Other Small Placers
Other small gold placers can be found in and around Ramona and Wynola. I can't give you exact or detailed information on these areas but I do know that placer gold was recovered below the location of the old Spaulding Mine at Ramona, according to historical records. You may have to do a bit of research, however, to get an idea as to where the Spaulding Mine was located. Gold was recovered for a time in small placers in the Wynola area, and at one point in the early 1980s I was able to gain permission from a landowner there to check the gravels on his property, but I don't recall finding much. Perhaps you will have better luck. Either way, I suspect that both placer areas (Ramona and Wynola) were "gobbled up" in the San Diego County real estate boom of the last 25 years.
Escondido and Low-Grade Ores
Additionally, low-grade gold ores were found in and near the Escondido area in the late 1800s or early 1900s. At one point a lode gold mine was worked just north and east of downtown Escondido. I am reasonably certain this mine site no longer exists due to the inevitable real estate overdevelopment, or if it does, it resides on private property now. Back in the mid-to-late 1980s I hiked up some steep hillsides just northwest of Lake Hodges (on the north side of the highway above Del Dios Canyon) and found numerous abandoned gold prospect or test pits that had been dug there. The ore did not look promising to my eyes, and although it was heavily iron stained I was never able to recover any gold from crushed samples. Nor was there any evidence of real mining activity at this location. Just prospect pits. But check it out if you can still gain access to that area....who knows?
Buckman Springs Placers
One placer area I am familiar with though, is Buckman Springs. My old mining club had a couple of placer claims at Buckman Springs. Where? If you pull into the Buckman Springs Caltrans Rest Stop and look across the way, you will see the old two-lane highway that also runs east-west (Sunrise Highway or Buckman Springs Road?) and just beyond that, a steep, unpaved road that climbs to the top of the hills there. If you take that road all the way to the top (you should be able make it with a 2-wheel drive vehicle in good weather, no problem) and continue on a bit, you are within the Buckman Springs gold placer area.
Sorry, I have no idea what the status of this gold location is these days, so ask around or research it before making the attempt. Additionally, be forewarned that the placer gold at Buckman Springs is typically pretty small and fine, so don't expect nuggets and coarse pieces. One more thing. This location can be thick with rattlesnakes in warmer weather so watch where you step and more importantly, where you reach or place your hands.
Gold at Black Mountain
I also found a decent amount of placer gold at a location near Black Mountain in the early 1980s as well, but neither you nor I would be able to mine this area now. The site is now buried beneath tons of asphalt, housing subdivisions, condos, and mini-malls, sad to say. Regardless, I wish you well in your mining endeavors in San Diego County.
(In the earlier version of this post I deliberately withheld some information on gold in San Diego County from you, the reader, for personal reasons. However, I see no valid reason for holding back such information any longer. Sometimes secrets need to be kept, other times not. J.R.)
Be safe out there.
(c) Jim Rocha (J.R.) 2008