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Treasure in the shallows
If you enjoy digging up coins, jewellery, or even gold on dry land, it’s time you thought about getting some gold from shallow water. Sure, there are a lot of things lost on dry land or the beach, but the majority of valuable items are lost in the water and are therefore inaccessible to land-oriented detectors simply because electronics and water don’t mix. But don’t despair.
These days there are numerous affordable underwater detectors readily available from leading manufacturers such as Garrett, Minelab, Nokta and Fisher along with those from lesser-known reputable makers. And of course there are those being turned out by rip-off factories in Guangzhou, China. Avoid these at all costs. Shallow-water treasure hunters have a lot going for them because of the laws of physics.
Heat expands, cold contracts. It’s one of those immutable natural laws. The human body is designed to function on dry land and works best at a temperature of 37 degrees Celsius or 98.6 degrees Fahrenheit. When the body enters the water it loses heat 24 times faster than on land. Any scuba diving manual will tell you this. As the body cools, the extremities shrink, fingers included.
That ring that was once a good fit now becomes quite loose as this shrinkage occurs. The body’s natural oils in combination with saltwater makes a great lubricant causing rings to slip off fingers. Unless you happen to have a detector with you at the time, there’s little chance of locating and getting the ring back.
Why? Well, gold has a specific gravity (SG) of 19.2, which in layman’s terms means it is a heavy element, much heavier than sand which has an SG of about 2.5. Because sand is comprised of particles, the ring, being heavier, will bury itself in a very short space of time making recovery almost impossible unless, of course, you have an underwater detector on hand.
People are vain and like to wear jewellery; it’s fashionable and trendy. Women and men both wear wedding rings. The woman might also wear engagement or eternity rings, both of which may contain precious gemstones.
While these gemstones by themselves will not elicit a response from the metal detector, the detector will pick up the surrounding metal, which could be gold, silver or platinum.
Next time you go to the beach, have a good look at the hands of swimmers and see how many people are wearing rings and entering the water with them. You’d be surprised. For some reason people just don’t take them off.
Mother Nature is now working on your side because a percentage of those people are going to lose some of their jewellery.
The variety of items found in the water boggles the mind. You can understand rings, watches, charm bracelets, bangles, gold and silver chains, pendants, medallions and coins, but reading glasses and sunglasses, hearing aids, car keys and mobile phones – seriously!
Once you decide to take up shallow water detecting as a hobby, in addition to your detector you will need to make or buy a special recovery scoop and also construct a floating sieve or screen out of an old inner tube (if you can find one in this day of tubeless tyres) and a suitable piece of wire mesh.
I use a motor cycle tube attached to a piece of 10cm interwoven mesh. Aviary wire has a tendency to come apart at the solder joints and if you have a very sensitive detector, you could find yourself trying to recover tiny bits of solder that have come away from the sieve.
Almost anyone can get into the water and start winning some gold. All it takes is the desire to succeed and a good dose of patience because at times you can swing that detector back and forth for quite a while without hitting a target.
Because there is also less junk in the water than on the beach, it’s safe to say that most targets will be good ones. There’s nothing quite like looking into the sieve and seeing a nice glint of yellow.
Almost every beach has what is known as a near-shore channel and an off-shore channel. Tidal movements scour these channels and at certain times, rings and other valuables which have been lost, maybe years ago, come within reach of the detector.
I say years ago because it is not unusual to find Victorian-era artefacts in the water. And many of those objects, lost years ago, are still waiting for someone to recover them.
The sea is our last frontier; it’s almost virgin territory to today’s detector operator. In Australia there are thousands of kilometres of coastline, thousands of places where people have swum, and the older the area, the more chance you have of finding something unique, unusual or interesting.
During the late 1970s, when metal detectors first started to make their presence felt here, a new gold rush occurred with people visiting the goldfields in the hope of finding nuggets the old timers missed. Now the gold rush is on in the water because there happens to be tonnes of it waiting to be recovered. With the high cost of fuel today, it’s more economical to drive to the beach than to head to the goldfields in the hope that you might find a speck or two.
Sure, there were plenty of people who were lucky enough to find good gold in the early days but those days are long gone. The majority of the big stuff was cleaned up years ago and traded for a new swimming pool, car or even house. And the Mines Department doesn’t replace the gold nuggets out of the funds it gets from your taxes. On the other hand, my 100-year-old bank is open 24 hours a day. I can go down there most times and with a little work and effort, make a withdrawal or two.
Davey Jones Bank doesn’t worry about paperwork either. Just a little effort and some research into tidal movements, channels, longshore drift and tide times and you could be making those withdrawals too.
There are certain things you will need first up apart from those already mentioned. For starters, you’ll need either a good pair of waist waders or a wetsuit. I prefer a wetsuit because a good 7mm suit will keep you nice and warm and is more streamlined in the water. Waders are all right but should a wave come along or you walk into deep water, they will fill up and you could be in trouble. A good wetsuit should last several years of continuous use so it’s a much better investment.
You’ll also need a sturdy pair of sneakers or wetsuit boots. You often dig up broken glass and unless you have some protection, you could end up with cut feet. Some kind of bag to put your goodies is a must along with another bag to put your rubbish in. If you put your trash in the rubbish bin, you won’t have to dig the same thing up time and again.
People do watch what you’re doing and will frown upon an individual throwing the junk back into the water. Be a good treasure hunter and do the right thing; if you dig it up, dispose of it in the bin where it belongs.
The best times to work are two hours before and two hours after low tide. This allows you to get into the channels where a lot of valuables accumulate.
I prefer to grid a channel by going back and forth across it. Depending on the detector you are using, this could mean having to continually retune as you go.
Other treasure hunters might prefer to search parallel to the beach detecting for perhaps 20 metres and then coming back. If you work it this way, remember to go to the deepest section first as you can always detect the shallower parts as the tide comes in.
Once a target has been located, pinpoint it by using a north-south, east-west crisscrossing method. The target is directly below the strongest signal. Should the target be too big, or near the surface, try lifting the coil to locate the exact target centre. Once located, place your foot behind the coil, remove the coil and use the digging tool to extract the target.
Here’s where the floating sieve comes in handy because the sand will go through the sieve leaving the target there for you to retrieve. It’s best to supervise this action because if you have a chain, it could easily slip through the mesh so it pays to keep an eye on things. Sometimes you’ll get targets that don’t show up in the sieve. If this happens it was more than likely metal trash such as a small nail or rivet.
But it would be a serious mistake to assume that any beach has been cleaned out. Valuables have been accumulating at any popular beach for more than 120 years and very few people have taken up this hobby and started to recover them. The sea bed can also change dramatically overnight. For instance, one day you’ll search for hours and get nothing, then, overnight, something happens and the next day you’ll have targets galore to pick up.
The best time to search is after a hot, sunny day. Go to the beach during the day and look for the area in the channels where most people are swimming. Go back during the evening, when everyone’s left the beach, and search these areas – you’ll be surprised at the amount of valuables you find.
There’s nothing to stop you working at night either. All you need is a good waterproof or underwater torch. Tie it to your sieve so you don’t have to worry about as carrying it. Just drag it behind you and use it only when you have to. The sea is like a giant Christmas pudding, the valuables being the fruit, the sand being the dough. It’s in a constant state of movement owing to tidal action. Hit the channels on the right day and at the right time and Davey Jones will open up his locker to you for a short while. It won’t last forever so spend as much time as you can in there and get what you can, while you can. The next time you detect the same area I guarantee it won’t be the same.
However, if you’re searching a lake or river bed, it’s a different ballgame because you have no tides to contend with and the object remains where it was dropped. There must be hundreds of old swimming holes around and with a little research it wouldn’t be too difficult to locate them.
A lot of shallow water metal detecting is done in the USA in rivers and lakes and some of the professional treasure hunters there have been known to pick up close to 100 rings in a day from these places.
Precious metals are hallmarked in one way or another and can easily be recognised from plated objects. For example, sterling silver is marked 925, while Britannia Silver, which is used on special occasions, is marked 958. With regards gold, 9ct is marked as 375; 14ct as 585; 18ct as 750; and 22ct as 916. Should you be lucky enough to get an item with 950 on it, you’ve hit the jackpot and got something made out of platinum, which is worth far more than gold.
On a lot of British jewellery there are other hallmarks which denote the mint in which the gold was assayed and a letter which tells you the year of manufacture, enabling you to date your finds. The year was put on for tax reasons. Several books are available on hallmarks and it pays to have one in your library because you could find a valuable antique without knowing it. Antique dealers love to get items for less than their real value so don’t let them profit from your ignorance. Do your homework.
Anyone wearing a wetsuit will find that the extra buoyancy caused by the neoprene rubber will mean they have to start wearing a weight belt with about 10 kilos of lead on it. Even with the extra weight, digging in deep water can cause a few problems especially on deep targets.
Detecting in shallow water is like looking for a needle in a haystack. One must listen carefully to the signals given off by the detector and learn how to interpret them. A good operator, after a short time, will be able to tell the size of the object, be it big or small, but there’s no way of knowing what the target is until you dig it up and it’s in your sieve. Stainless steel digging tools are the best for several reasons. They are light in weight, they cut through the sand faster than mild steel, and they are stronger. On the other side of the coin, stainless steel is more expensive than mild steel and harder to drill and work.
Water causes a lot of drag, especially when the tide’s running. Don’t fight the drag, instead, try to work with it. That drag is good in many ways because it slows down your search meaning you become more methodical. Anyone trying to work too fast in water is not only missing good targets but also putting undue strain on his/ her equipment and also tiring themselves out a lot faster.
Should you arrive at a beach and find a lot of holes already there, don’t worry, there are still plenty of targets that were missed. Check out the holes as you’d be surprised what other operators leave behind. Interest in shallow water metal detecting in Australia is on the increase mainly because of the huge amount of valuables being recovered by those who have already taken the plunge and invested in an underwater metal detector.
I say invested because underwater detecting can be a highly profitable hobby. Many years ago I was told about one bloke who went out and found a four or five ounce gold bracelet containing 18 diamonds. It was valued at more than $8,000 in today’s currency. Not only that but the same guy recovered a diamond ring, with one of the diamonds topping one carat.
If you can get your hands on it, read the book Diamonds in the Surf. It’s only a cheap paperback and Amazon has copies. To help you understand more about the sea, Coasts: An Introduction to Coastal Geomorphology by Eric Bird, is full of useful information.
Here’s something to think about. Say for example, over the course of one year, one ring was lost on a beach per week. That’s 52 rings a year. Yes, I know people aren’t swimming there in winter but it’s an average we’re talking about. Swimming became very popular at the turn of the last century so we have 120 years in which items have been lost. That one beach could have as many as 6,240 rings in it.
Given the average weight of a gold wedding band is between three and four grams, this means there could be up to 24,960 grams of gold buried in the sand on that one beach, or, if you prefer, 802.48 ounces. There are more than 24 popular swimming beaches in Port Phillip Bay alone, so in theory there should be about 19,259 ounces of gold in the bay. And that’s just from gold rings!
This figure is probably conservative because on any hot summer’s day, thousands of people flock to the beach; some are so crowded you can barely move. How many rings are lost in one hot day, no-one really knows but it’s far more than one.
People do lose other things too, such as watches, chains, pendants, coins, bangles, bracelets. So the amount of jewellery in Port Phillip Bay alone would not be a matter of ounces but tonnes. During a trip to one of these beaches with two other underwater hunters, one guy I know bagged four rings, all gold, with a total weight of 39.5 grams. And it probably didn’t make a dent in the amount of gold in that area because it’s constantly being replaced by careless swimmers. Maybe it’s time you opened an account with the Davey Jones Bank.