Treasure Talk

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The GPX 4800 with the Coiltek 18” Elite

April 04, 2016 04:09pm

Gordon Heritage
Gordon Heritage metal detector professional

I sometimes wonder if a new product truly out performs previous designs. Or is it that you rush back to your favourite detecting sites, full of confidence after reading initial reports... and then find targets missed on previous hunts that were within the capabilities of your old machine.

About a year ago I received a Coiltek 14" Elite mono coil. I could instantly see a marked improvement over my grey 14" mono coil. Testing it over a hoard site, I could detect a silver penny at the same depth and intensity as my old Coiltek cream 16" mono. I reported back to Trevor at Coiltek, telling him I was impressed, but would be more interested in a larger coil of say 18". This would be the best size coil for finding the greatest prize of all for UK detectorists; Celtic gold staters.

These coins weigh an average 6 grams and usually consist of 90% gold. They date from 150BC to about 50 AD in the UK. I sent Trevor one so he could test new coils with it…This has proved to be a good investment.

The day finally arrived when I received notification that the coil was waiting for me to collect from Royal Mail. Once I paid the import and VAT I hurried home with a large flat box. Removing the coil I was surprised how big it looked, and bolted it straight onto my GPX 4800. I decided to drive immediately to a field that had produced Roman and Celtic coins. There was an area that had been heavily detected, where all targets had been removed; ferrous and non-ferrous, on previous searches with an 18" mono coil.

There were no targets at all remaining in this area, so imagine my surprise when I marked 5 targets within just a few minutes, "surely one would be good" I thought to myself. The first faint target was dug in the first spade full of soil, so I knew it was likely to just be a small bit of rust, so back-filled the hole. I moved on to the second target, digging down to 18". Probing the hole with a pinpointer was fruitless, and to be honest, I thought it must have just been ground noise so back-filled the hole. But when I passed the coil back over the filled hole, I realised the faint target was slightly off where I had dug the hole. So I re-dug and extended the hole in the direction of the target. As I scooped out the loose clay at the bottom of the hole, I caught a glimpse of gold, the edge of a gold coin in the bottom of the hole. Carefully releasing the coin from the wet clay, I was soon holding a lovely Remic gold stater dating to 54 BC.

The following weekend I returned to the site of gold stater hoard in Norfolk. The hoard was of a type of gold stater called "Norfolk Wolf" because of a Wolf on the reverse where normally a horse would be. The site had been stripped with a digger and searched with a GPX 4500 fitted with a 16" mono coil. 21 coins had been found previously, and because of how well the recovery had been conducted, chances of finding another one were low.

I worked the site marking all targets with blue line paint; dots for loud (shallow) targets and circles for weak (deep) targets. While my detecting partner (Dean Crawford) followed up digging the marked targets that couldn't be detected with an Explorer II. He dug a mix of iron and non-ferrous targets, mainly small lead shot, and bits of shotgun cartridge ends.

One of the targets not detectable with the Explorer turned out to be very deep. Dean had opened up a large hole to 18" and asked me to check the signal with the GPX 4800, which I did, it was still dead centre in the hole. We then took turns digging down to two feet and finally the pinpoint probe started to detect it. Dean then carefully dug deeper, into what looked like rusty soil. He put the pinpointer into the soil and it screamed indicating a target was close. Dean exclaimed it must be iron because of the rusty looking soil and scooped out. Then jabbing the probe at the spoil he said "There it is, iron". I picked up the lump he referred to and the soil fell away to reveal a lovely Norfolk Wolf gold stater, dating to 50 BC. Dean then placed his spade into the hole and marked the depth on the handle. The mark was later measured at 26", the deepest coin either of us had ever dug.

In the beginning of this blog I wrote that I wasn't always sure if the success of a new product was always because it was better, or if it was merely that instils the inspiration to return to old "good" sites with renewed vigour, that brings success.

But when it comes to Coiltek's new 18" Elite mono coil, there's no doubt in my mind. This coil is significantly more sensitive at depth than anything I've ever used before.


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