The hands-on part of my field test was a rewarding experience that yielded 13 coins dated between 1851 and 1910, plus a silver nugget, as well as numerous very old artifacts. Over half the coins came from a site that I and others had searched before; the nugget came from an area long considered "'worked-out." But first, meet White's Liberty Di.
The Di is the third in White's lightweight Liberty series and the first of these to have, Visual Discrimination Identification - in other words, a meter. But to me, its two most important features are automatic GEB combined with AutoTrac and its ease of operation and light weight.
Automatic GEB is just what it says; a truly automatic ground balancing system that responds to the mineralization of the ground, rather than factory presets that all too often are characterized 'as being "automatic."
Its operation is very simple. Hold the detector as you would while searching and adjust the position of the coil so that it is flat on the ground; then tighten the thumbnut that holds the coil just enough so that the coil will stay in this position. Now, turn on the detector via the SENS knob and set it and DISC to the letter "P" surrounded by a triangle which appears on each scale. These are White's suggested starting Positions and will work under normal conditions. Raise the coil to hip height, squeeze in the trigger and move the AGEB switch to AIR. The detector will, respond with a beep. Still squeezing the trigger, place the coil on the ground and move the AGEB switch to GRND. Hold the coil steady until the detector gives another beep. Still squeezing the trigger, raise the coil back to hip level. If the detector's hum remains steady, it is ground balanced and ready to begin searching. Releasing the trigger changes the mode to GEB/DISC, the Liberty Di's primary search mode, and activates AutoTrac, which responds to changes in mineralization, thus maintaining ground balance.
If the hum doesn't remain steady, balancing may have been attempted over a target and simply moving a short distance away and going through the procedure again will produce a steady hum. Otherwise, some counterclockwise adjustment of the SENS knob - as little as possible - and rebalancing may be necessary. In any case, a steady hum from ground to hip height is required before searching begins.
The Liberty Di weighs 4.8 pounds with batteries, compared to 5.4 pounds for the 6000 series, despite having an armrest support about a foot long with a padded armrest. White's has accomplished this by using A.B.S. high impact plastic for the control box casing, handle, armrest support and armrest. But it is much more than the relatively small difference in weight - approximately II% - that makes the Liberty Di SO easy to use.
Anyone who has used the traditional lunch box type detector with a handle knows that the effort required to hold and swing the instrument is concentrated in the hand and wrist. In time this can become tiring, particularly to older people or those with physical problems. Thanks to the Liberty Di's armrest, the effort is spread out to include the entire forearm. This, Plus extremely good balance, adds up to a detector that's easy and comfortable to use over extended periods of time.
The Liberty Di offers GEB/DISC and GEB/All Metals mode. The automatic GEB and AutoTrac operate in GEB/DISC only. In GEB/All Metals the detector is manually ground balanced.
Manual ground balancing is also possible in GEB/DISC by placing the ground balance control switch on LOCK as soon as the detector has been ground, balanced, although White's does not recommend this.
The heart of the detector is the control box, which is mounted to the top of the handle and may be detached for Storage Or transportation.: It contains all the controls, a low battery alert light and a meter similar to the ones found on White's 6000 series. Although considerably smaller, the meter performs the same four functions. The Visual Discrimination Indicator (VDI) does an adequate job of indicating the probable composition of various targets and predicting the denomination of various U.S. coins. I found out in a very pleasant way that it's calibrated in terms of modem coinage; an 1851 large cent - made of bronze and slightly larger than a quarter - that was found, registered as a quarter. A third scale shows probable depth when the detector is in the All Metals mode. At the top there is a scale graduated from 0 to 100. Its purpose is to determine, by means of a bench check, where various commonly found targets will register on the meter.
I had the opportunity to take the Liberty Di to Austin, Nev., in the old Reese River Mining District, which has become one of my favorite treasure hunting sites. It was the scene of a great silver strike during the 1860s, but the mines began to dry up around 1885. U.S. Highway 50 runs through it, otherwise it would probably have become a ghost town years ago. Austin became a headquarters town for many mining ventures, and the area is dotted with ruins that have never been searched with a metal detector. Again, a tip of the sombrero to Austin turquoise miner Al Lombardo, for pointing out the likely treasure hunting site, ("There's No Help Like Local Help," Lost Treasure, Jan., 1986).
Most of my successful hunting in the Austin area has been in GEB/MAX or its equivalent - depending on the detector's nomenclature. The theory is that the good coins have been there for a long time and are very deep, so a maximum signal is required. This means digging a lot of targets, but anything found may well be 100 years old or more and of some value for that reason alone. The excellent 21-page operator's manual that comes with the Liberty Di points out that GEB/All Metals produces the strongest signal, so that was the mode I started using.
The theory falls apart if there's ever been a wooden structure in the area being searched. Building nails are, to such a site, what pull tabs are to today's public parks, and one can get just as frustrated digging them up. One location produced a number of good artifacts, including oxen shoes, but also lots of nails. I soon found that the Liberty Di was capable of a signal that indicated a nail, even one located six inches down, as clearly as if it had been written in neon letters. Moving the, coil across the target from a number of directions would at some point produce a double signal.
Later that day, a friend and I searched among the tailing piles on Lander Hill, the location of some very rich silver mines, also in GEB/All Metals. A strong signal that gave off a double beep when pinpointed, but was too loud to be a mere building nail, yielded a bent rail spike which was too small to have been used on even a narrow gauge railroad. A regular pattern of identical signals, which we didn't dig, suggested that, at one time, there had been an ore cart railway there to service the mines, but that the rails and ties had long since been tom up and the spikes left there. One of Austin's old timers later confirmed this.
So far I'd shown that the Liberty Di in GEB/All Metals is an excellent artifact finder and learned to distinguish the sound of a building nail. I had a considerable collection of broken mining tools, construction fittings, square nails and some objects as yet unidentified - all badly corroded from decades of being in the heavily acidified soil. There was even a spent bullet which had splattered against a rock, but retained enough of its shape to be identified as of .44 calibre. But as yet, no real goodies.
The first glimmer of hope came when we went to a spot which in past years has produced silver nuggets some weighing more than a troy ounce - although recently it has seemed to be barren, filling up with soil.
I Silver nuggets are formed by later volcanic action in a silver-bearing area. The hot fingers of lava, coming from below, melt the ore into nuggets and drive them up towards the surface, where they cool. The Reese River Mining District is one of the few places in the world where they are found.
I began searching the edge of a former nugget-producing area in the usual GEB/All Metals, but received indications of nails. Having enough of these, I reset the ground balancing by switching over to GEB/DISC - thus activating the AutoTrac - and set the DISC just above 3 to tune out the ferrous metal and still not miss a nugget. After about ten minutes it paid off with a signal that showed on the meter as a dime, and we found a small nugget about 8 inches down. It was the only one we found, but it was also the only one found there for a long time. It weighed well over two pennyweight, about average for Reese River finds. Silver nuggets are worth about 30 times the spot price of silver, due to their rarity. Lombardo sells them in a jewelry store, at the very east end of Austin, that he owns. He thinks that taking down what had been the nugget- producing area two feet with a bulldozer will produce another layer of them.
We were sufficiently impressed with the Liberty Di in GEB/DISC that the next day we searched in that mode at an abandoned gold mine where last year we found two Indian head pennies and an old, bawdy house token using two metal detectors, both putting out their strongest signals. We quickly started finding coins and eventually unearthed three Indian head pennies dated 1900, 1901 and 1902; three V nickels dated 1890, 1900 and 1910; and a 1904 half-dollar. Seven coins with one detector where we had only found three the year before using two! The only thing I can think of is that the mineralization at the old mine changes so rapidly that the two detectors we used in 1985 were properly ground balanced only for a few feet at the beginning of each search. In retrospect, all three finds were made almost immediately - then, nothing. The Liberty Di's automatic ground balancing, on the other hand, evidently was able t6 keep up with the changing mineralization and kept finding coins which had been there all the time.
Back in the hills there are the ruins of a stone building measuring about 20 x 25 feet that even Lombardo didn't know about. His assistant, Danielle Kohler, spotted it while cross-country skiing last winter. We took the Liberty Di there the following day and really hit pay dirt. The flooring, which no longer exists, had probably been planks laid over the earth and anything that had been dropped or fallen through the cracks was, we hoped, still there. We found in one comer a large quantity of building nails that had never been used and weren't appropriate for that type of structure; so we deduced that the building had been used as a store at some time and there was no telling how many more nails were there. We started searching in GEB/DISC with the DISC again set to reject iron.
Our finds were an 1851 large cent, an 1864 two-cent piece, an 1895 Indian head penny, an 1857 Seated Liberty quarter, an 1892 half dollar and a 1897-S silver dollar. They were quite evenly distributed throughout the area we searched. We'd started fairly late in the day, and we needed good daylight to make our own road out, so we reluctantly left most of the ruins unsearched. By statistical projection, there are still 12 more coins there.
All in all, I found the Liberty Di to be a very satisfactory and easy-to use detector. AutoTrac had enabled the detector to locate seven very old and deep coins - and possibly the silver nugget - that had been missed by two considerably more expensive detectors that didn't have that feature. Both were operating at maximum output, which no doubt exceeded the Liberty Di's, but their responses were masked by ever changing mineralization, which AutoTrac was able to adjust to.
However, I encountered one major problem. After about eight hours of operation with the rechargeable battery, the detector became unstable. I suspected the battery was getting weak and very belatedly the low battery alter light blinked once, and only once. If I hadn't been looking right at it, I never would have known. My solution was to finish the day with fresh alkaline batteries and " to put the rechargeable one on the charger for eight hours that night. White's has had a completely reliable battery check on their other detectors for years, so I can't understand why they would retreat to an idiot light on the Liberty Di.
I also found an alternative way of detecting weakening batteries. Go through the air to ground balancing routine and listen closely to the beeps. If the air beep starts to break up or the ground beep takes a long time in coming and then is weak, it is time to change batteries.
Also, the Liberty Di's earphone receptacle accepts the 1/8-inch mini plug. So, if you are planning to use an earphone with the familiar 1/4-inch plug, an adapter is required. These are generally available at electronics stores, but the one I bought didn't cut off the speaker, as it should have, and I had some trouble keeping it in the receptacle because of its weight. However, White's is offering their own adapter through their dealers as an accessory and these are preferable to those bought elsewhere.
For more information, contact White's Electronics, Inc., 1011 Pleasant Valley Road, Sweet Home, Oregon 97386.