Classification:

In order to pan down to pure gold (ie, virtually no contaminants such as black sand or lead) pre-classification is required. This is so because in the early stages you do not want to lose any gold to turbulence and the final stages of isolating the gold can only be accomplished with minimal turbulence. Particles of unequal size create unequal water action (eddies and swirl) known as turbulence.

Types Of Pans:

Pans come in various sizes and configurations. The best pans for rapid front panning are steep sloped, narrow bottomed and have riffles built in. The best pans for back panning are shallow sloped, have no riffles and plain, wide bottoms (ie, no drop zone between the flat bottom and the sloping sides -- just a single crease where sides and bottom connect).

Front Panning:

The rapid settling of gold and preliminary elimination of impurities involves front panning. The basic idea is to scalp off successive layers of unwanted material over the front lip of the pan until no further scalping is practical. The best way to create upper zones free of gold (and thus ready to scalp off layer by layer) is to place the entire contents of the pan in a state of separation, allowing the heavier gold to sink faster towards the bottom. This can be done by vigorously shaking the entire contents of the pan. Momentary separations can be achieved by banging the sides of the pan against something solid. It is important when scalping off a layer to do so on an even plane (where the direction of movement is parallel to the bottom surface of the pan).

Back Panning:

This is the least understood and most difficult to master of all the panning principles. Unlike layer removal, which works best with particles of grossly differing weights, the idea of back panning is to draw off particles of comparable weights. To do so the idea is NOT to create a state of complete separation. Rather, the aim is to maintain the capillary cohesion of the mass while carefully drawing off the slightly lighter particles toward the back of the pan. See the web site article for details. Any PCSC member who would like a free demo or to learn how to master this technique may contact me at any club event or privately.

LAST MONTH'S (APRIL)   ANNOUNCEMENTS

Prospecting Tip Of The Month:

A common problem that faces prospectors (using either a sluice or a drywasher) who are attempting to maximize their recoveries, is how to establish the proper angle of their sluice or drywasher riffle tray. The conventional procedure is based on a prescribed drop angle in terms of inches per foot (e.g., 1 to 2 inches of drop per foot of length of sluice). This certainly is a helpful guideline, but it is insufficient for those of us who desire to fine tune for maximum recovery -- especially of fines. I came up with the following insights and techniques after I watched a dear friend of mine (Ed Gulley) use a copper penny to determine whether our sluice was running at too hot of an angle. First, it must be remembered that there are two important angles (vertical and horizontal). If a sluice or riffle tray is permitted to tilt off horizontal level, then losses will result due to induced swirl and loss of laminar flow (sluices) and due to unequal riffle loading and spillage (riffle trays). Sluices and riffle trays may sag off center over a period of time. A simple solution for establishing initial horizontal level, and also for noticing sag over a period of time, is to glue a flat bubble level on a horizontal plane of your sluice or employ a small level across a riffle tray. Second, vertical angle must be adjusted to be consistent with initial water velocity (in sluices) and type or size of material (in both sluices and riffle trays). Note that the specific gravity of pure copper is approximately one-half that of AU. Thus, by stripping some copper wire and using my bench grinder, I create a sufficient amount of tiny, shiny copper filings that I take with me into the field. When fine tuning my sluice or riffle tray I count out about 5 or 10 of these tiny filings and then run them through. In either a sluice or riffle tray I can then tell whether all of the filings are trapped. If so, then I will be maximizing my recovery of (twice as heavy) AU. Third, I glue plastic curved bubble levels (the kind used to level an RV) to each side of my sluices. Over time I note the range in which the air bubble floats between max and minimum recovery planes. This enables rapid set up and adjustment of sluice angle. Fourth, if the gold is running fairly large (ie, not much evidence of very fine gold) and the objective is to process max volume, then larger copper pieces are used. I fashion these to resemble the shapes of nuggets by using wire cutters to clip off small bits of varying gauge copper wire. Some of these I pound flat with a hammer. Others I leave somewhat round or rod-like. These larger coppers allow me to ascertain maximum vertical drop. Fifth, all these copper bits are perfect for practicing panning -- a necessary skill for separating my gold from concentrates. If any PCSC newbies would like to accompany me in the field for a demo and time permits, just let me know.
Martin Milas, PCSC President

(MARCH)   ANNOUNCEMENTS

Prospecting Tip Of The Month -- Putting Your TP To Work!   Okay, we all know what toilet paper primarily is for.  But did you know that it also can be an extremely useful aid in locating gold nuggets?  I came up with this technique some while ago while detecting with a Minelab Extreme on our Clark Claim.  One of the potential problems we face anywhere, but particularly on the Clark, is the presence both of very tiny nuggets, a ton of hot rocks and significant smallish trash.  Thus, when employing a pulse induction detector you encounter a number of faintly heard signals that are extremely tedious to pinpoint.  So instead of burning up precious time attempting to recover these small targets with the Minelab, I began marking each spot by tearing off a single sheet of TP and holding it down with a stone.  Later, I switched to my Gold Bug 2 and retraced my steps.  The TP really stands out compared to other marking techniques -- especially under the dimming light of a fast setting sun.  Even if a few little sheets get away, the tissue does not endure for very long (if the local rodent population doesn’t use it for nesting, the harshness of the elements soon causes it to disintegrate, thus leaving no trace behind).  And, of course, it is nice to have some TP handy for those other unexpected needs.  Note also, that in heavily populated areas, such as our Red Chispa Claim, there are a lot of Lookie Loos potentially watching.  If they see you digging a number of targets you can be sure they will descend  on your spot later like a flock of hungry crows.  So I often do not engage in much actual digging when others are present.  By the time the sun gets ready to set, the landscape clears of other human life forms.  This is when I do my serious recovery work, often with a headlamp in total darkness, remembering to carefully cover over the places I have worked so hard to develop, leaving no clues for others to exploit in my absence.  I use TP as temporary markers in this setting because it only takes a moment to anchor a small sheet of TP and then move on.

2008 Awards Banquet:   Each February the PCSC Annual Awards Banquet has brought us together -- not just to recognize the individual contributions of all who serve this club so well -- but also to enjoy an evening of camaraderie and good food.   Chuck and Chris Carfrae have been among the great club stalwarts over the years who take the laboring oar.  And once again they made this a high point in our social calendar despite a serious medical setback for Chuck who had to sit this banquet out.  We missed you, Chuck, and we wish you a speedy recovery.

March Program:   Yikes!!  I will be in Texas during late March.  But Joe Keely, our Program Director, has been arranging an interesting March program.   Tex, as Vice President, will run the meeting in my absence.

(FEBRUARY) ANNOUNCEMENTS

Looks like our February meeting will be the place you want to be if you ever wondered what hard rock mining is all about.  Bob Dunkin grew up in Twentynine Palms.  On his sixth birthday his father informed him that it was time to learn about gold mining and took him underground on a tour of the Gypsy Queen, one of the area’s still productive mines in the early 1950’s.  The gold bug bit him hard and ever since that day Bob has chased the yellow metal close to his home in the Dale Mining District and as far afield as Alaska.  He has owned and operated his own mines, was in the process finally of making a fortune and then lost it all in legal fees fighting the government.  Needless to say, he is a great source of information and is a wonderful story teller.  I promise that you will not want to miss this one!  Best of all I have recruited Bob to join our Club.  In the event the Club is interested in picking up some additional claims, he could be a valuable asset.   Know the difference between a hanging wall and a foot wall?  Know why this is important?  No?  Well, be sure to bring these or other questions.  I’m sure that Bob will oblige you with answers that only can come from over 50 years of intense experience of handling dynamite, dealing with rattlesnakes and maybe most scary of all, dealing with our own government.

Tide Activity

We have some big tides rolling through Southern California in February.   The series of big swings begins around Valentine’s Day and progresses into high (or should I say “low”) gear at 12:40PM the day of our annual awards ceremony and dinner (Feb. 16th).  The next four days in a row the high tides will be running around 6 feet plus in the mornings, then draining back out for lows of -1.3 feet occurring between 1 and 3 in the afternoon.  Sooo...if luck is with us, maybe some or all of those days we will also get some big wave action -- especially with periods of 8 seconds or less.  These are the conditions that can make for metal detecting heaven -- as long as you don’t get caught in a rip!  I for one plan to be ready for action.

Classified Ads

How many of you would like to add a classified ad section to our Club web site?  A place you can post a “want to buy” or “want to sell” ad?  For free.  Let’s talk about this at the February meeting.  If enough interest is shown, then we can make it happen.  This and other suggested ideas will be discussed after the program during the “new business” portion of the meeting.