(Old arrastre in the Rand Mining District of southeastern California.)
I'll be tying up a few loose ends in this post, including some info on desert gold and any tips I may have missed along the way in this series. So hang in there.
Desert Gold Attributes
In the broadest sense, gold is gold no matter where it comes from or where you find it, wet or dry. But that's where generalities end and specifics begin. There are distinct differences between desert placer gold and the gold you typically find in a running stream, including the fact that most desert gold is coarser than its wet placer cousin. No rocket science involved here, of course. In a running stream gold is tumbled, pressed, and worn smooth by hydraulic action and abrasion but in desert environments that erosional factor is intermittent (or missing entirely in some instances). This coarseness holds true even for many very small pieces of desert gold...when examined under a jeweler's loupe or magnifying glass very little wear will be evident in most incidences and gold surfaces will appear broken, rough, or even "spiky" at times. Also note here that placer gold that is consistently and significantly coarse may also mean that it's nearer the source (outcrop, ledge, vein, stringer, etc.) and has not "traveled" very far.
Gold Prospecting Books
Desert placer gold is also more prone to "contaminants" such as copper, iron, silver, and tungsten to name the most common culprits. In general, this means the purity level of desert placer gold is often less than that found in wet placers...but NOT always. I'll use the Old Placers District of the Ortiz Mountains (near my home) as an example: High desert placer gold from the this area runs about .917 fine out of a possible .999 purity level, an amazingly high purity for dry or desert placer gold...in fact the highest purity desert placer gold I've ever recovered. The Old Placers are a bit of an anomaly in this regard...most desert placer gold will run from the .725-.850 range, generally speaking. As long as it's gold, I'll take it either way!
Off the Hook?
Those of you who are primarily desert prospectors and miners and who commit the bulk of your mining time to dry washing and nugget shooting know how contrary desert gold can be. Rarely does it follow the nice, neat deposition principles that govern gold in running streams (sometimes it does...but most of the time it doesn't). This fact can drive you crazy at times and increase your mining frustration levels tenfold. This is one reason I'm always harping about "thinking outside the box" when it comes to locating and recovering desert or dry placer gold. Your fundamental gold prospecting and mining knowledge will serve you well up to a certain point and a certain point only when it comes to desert placering. After that, you'll need to improvise and remain flexible in your outlook.
(Dry placer gold claim.)
Made in the Shade
Repeat after me: Gold mining is not for whiny voiced wimps, cry babies, fat little honey boo-boos, lazy asses, or any other Darwinian form of non-hacker...have I not said this many times before in Bedrock Dreams? Yep, and it remains as true as ever. But dry placer or desert gold mining takes the cake as far as throwing the worst your way. I've seen more than a few wet placer miners toss in the towel in the desert and vow never to return (and many didn't). They bitched (and bitched) about the heat, the lack of shade and water, snakes, assorted insect vermin, dry winds, and being forced to eat sand, dust, and grit while bucketing material and feeding a dry washer all day. By the same token, they also failed to see the wondrous beauty of the desert and its delicately balanced environment, not to mention desert gold. In other words, they had no respect. So why would the desert respect them in return?
My best to all you "desert rats" out there!
(c) Jim Rocha (J.R.) 2013
Questions? E-mail me at firstname.lastname@example.org