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While hot rocks can be incredibly annoying, they are actually a good indicator that gold may be nearby. As most experienced prospectors know, the yellow metal likes to hang out in highly mineralized ground. In fact, the worse the soil is and the more hot rocks there are, the better the odds of walking over a nugget.
Learning to deal with hot rocks does take patience, but with a little practice you’ll have a handle on them in no time. Here are a few tips that I have found useful for dealing with them:
If your detector has an adjustable Gain, try reducing it and elevating the coil slightly above the ground. This will cause a loss of some depth and sensitivity, but may be more preferable than listening to the constant zips and boings of the hot rocks.
Hot rock infested soils such as this are very likely to contain gold
If you are running a VLF, or one of the earlier SD or GP Series detectors, your best bet will be to use a DD coil. The DD configuration will substantially help reduce the effects of hot rocks and ground noise. If you happen to be using one of the newer GPX models, you have more options. With the new soil timings found on these machines it is possible to re-work hot rock infested areas using the Monoloop coils. I have found much gold on my old patches by using the Smooth, Enhance and the newest Fine Gold timing (GPX 5000 only). These timings are incredibly powerful tools, and are making it possible to recover gold that has been hidden for decades beneath a veil of noise. If you own any one of the GPX Series machines, I would highly encourage you to pay another visit to any site that is plagued with hot rocks. If you happen to be one of the first detectorists to hunt it you could do exceptionally well.
Many times hot rocks can be tuned out by ground balancing directly over them. This may eliminate the hot rock, but in turn cause the ground to become noisy. Therefore I do not recommend this practice. I find it best to simply balance to the soil and deal with the hot rocks as they come. This usually entails kicking them aside with my boot or simply tossing them off into the bushes. The easiest way to deal with hot rocks is to simply memorize what they look like in a particular location. This way you will be able to quickly recognize them when you hit them. Fortunately the hot rocks in any given area tend to be fairly homogenous, so you should only have to memorize a few different types.
Large negative hot rock detected in California's Mojave Desert
Something else worth mentioning is that hot rocks can mask a nugget. I have found many little nuggets here in Arizona hiding directly below them. So, if you hit one and for some reason it doesn’t sound the same as the rest, you should move it out of the way and check the ground beneath. A general rule is, if the hot rock is not too big, kick it out of the way. Or, “When it doubt; kick it out!”
I don't enjoy listening to hot rocks anymore than the next operator, but as I mentioned above, I do like seeing them. If you find yourself in an unusually noisy patch of hot rocks, slow down and work the area very carefully. These spots do require extra effort, but you never know, that next signal you get could be the start of a new patch!
See you on the goldfields!
Chris Gholson Arizona Outback - Minelab Authorized Dealer
Detecting in NE goldfields of WA it always pays to check hot rocks. On many occasions gold has been found coated with iron stone.
Dug in a creek for this one and almost gave it the flick.
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