HOW TO TEST THE EFFICIENCY OF YOUR METAL DETECTOR
This is a very necessary step in order to avoid coming home with empty hands after a day of hunting in a good spot.
Manufacturers around the world praise their products highly... it's only natural.  It is up to the consumer, however, to verify that what is promised in the advertising is actually true.  The same thing happens with the people who distribute metal detectors, so you need to know a few fine points before you buy, which we are about to let you in on.  In the first place most of the distances which are advertised as the reach for metal detectors are measured above ground ... to detect something at the same distance underground is another story.  In the second place, the efficiency guidelines for much of the equipment are set when the equipment has attachments such as sophisticated electronics that are extremely sensitive such as oscilloscopes or microamperes which certainly will react to very low frequency signals.   The reality is  very different when you go out into the field to find targets which are buried deep in the ground.
Therefore, in order to know more about your metal detector and check to be sure that you will not pass right over a good find without receiving a signal (collector's items from the Civil War, a vase full of coins, antique bronze pieces, gold bars, hidden savings...) put your detector to the test as follows:  get a plain 33 centiliters beer or soda can, this is a universal target which is used by many to check their equipment for depth efficiency.  As a quality control check for your device and as a means of comparing it's strength to that of other detectors, we suggest that you use this universal target since it is approximately the same size as what would be a small hidden deposit (which can be worth lots of money!). 
Find a neutral zone (far from a residential area) and before digging the hole, go over a one (1) meter circle with your detector to be certain that there isn't anything already in the ground that will set off a signal.  You can go into the woods or to the middle of a meadow; sand dunes are ideal for this test.  Make a hole 50 cm. deep, measure it before laying the can at the bottom horizontally... of course, drink the contents before you bury the can, you may lose it!  Fill and cover the hole, packing the ground so it is again as dense as the surrounding area (this is important in order to avoid false signals).
Turn your device on, adjust it to the maximum and start your search.  If you do not receive a clear signal as you go over this pre-set target, which is quite large and not very deep, forget about ever finding anything really interesting.  You may find small objects that someone has lost but not the really worthwhile booty because those items have purposely been  buried deeper and they are out of the reach of your metal detector.  
If you would like to know more about how to detect what is to be found deeper in the ground and the best specialized equipment, please go to our page "Deep Metal Detection".
NEVER FORGET:  Valuable items will be buried deep in the ground.  Statistics show that more than 85% of valuable deposits are hidden between 60cm. and 1.2 meters below the surface. Pulse Induction detectors are the ideal mechanisms for this type search and really indispensable if you plan to hunt seriously and deeply to find  war booty or relics, silver or gold deposit, antique bronzes, hidden jewels, treasure chests or weapons.
gold candlesticks
Two gold 19th century candlesticks which were found using the Deepers Detector -  75 cm below the surface - border Switzerland / France.