(You never know what's waiting for you on bedrock.)
In this post I plan on discussing "plunger" type suction tubes, crevice vacuums, hand (or mouth) operated suction devices, and anything else that comes to mind that fits into one or more of these categories.
"Plunger" type suction devices: Often called "gold suckers," "hand dredges," or simply hand pumps, this type of device acts in much the same way a bicycle pump does. Typically composed of a length of PVC piping, a hand-driven plunger, and an array of different-sized or configured tips, these little gems work quite well. In fact I own two of them myself.
The nice things about hand-pump suction devices like this are their simplicity and ease of use. You place the tube's tip or nozzle into a crack or crevice and then draw the plunger upward to suck up the gold-bearing material. To expel the same material you simply place the tip into a gold pan or better yet, a 5-gallon bucket, and then push the plunger down. Once you do this enough times, you develop a rhythm of sorts and can really kick some low-water bedrock butt using one of these units.
("Gold Sucker" brand plunger suction device.)
It goes without saying that plunger type gold suction devices can be very useful when working low or shallow water bedrock conditions like those impacting California and other parts of the west these days. If you're flush they're pretty cheap to buy and if you're too cheap (or broke) to buy one, there are numerous do-it-yourself (DIY) plans and illustrations online so you can build your own. The total cost on your end if you choose to make your own with brand new materials? About $25.00 (USD) give or take a few bucks either way.
Crevice vacuums: I've seen these used mostly in dry placer locations too many times to count over the years. I can't really speak to their overall efficiency except in one major exception (the Aussie CreVac), but they seem to part of many small-scale miners' arsenals. You can buy retail models powered by electric motors or if you're a DIY type of guy or gal, rig one up that suits your own needs. With the exception of the CreVac, most of these vacuums are meant to be used in dry bedrock conditions and their housings can't be submerged or become wet for obvious reasons.
Hey, remember those old, battery powered Black & Decker hand-held vacuums for your car? They were bright orange with a handle and had a twist or pop-off housing where the dust and dirt gathered. Well here's a little story for you from my early mining days. Some 32 years ago I was still learning the ropes and was a member of a small but lively little gold prospecting and treasure hunting club (that was back in the days when I still found value in groups and crowds).
Anyhoo, one weekend at the Potholes District near the Colorado River and not far from Yuma, Arizona, I watched with no small measure of wonder as the wife of one of the other members used one of those little hand-held Black & Decker jobs to suck material from fine cracks in bedrock. She was very careful and methodical, taking her time working those minuscule cracks and then dumping that little bit of dirt into a 5-gallon bucket. Despite my own relative inexperience at the time, I smugly reasoned that she didn't have a rat's ass chance of coming up with any gold except a fleck or two. Boy, was I wrong!
(Here's what she was using...)
So the moral of this little tale is that crevice vacuums can and do work. I myself have never used one except the CreVac, which is really more of a mini-suction dredge device than it is a crevice vacuum per se. But as I just pointed out in my little parable about the smart lady miner and the dumb ass, these units have their place and time and it surely wouldn't hurt to have a unit along these lines if you're considering working dry low-water bedrock.
You'll have to make that call though.
(c) Jim Rocha (J.R.) 2014
Questions? E-mail me at firstname.lastname@example.org