In 2016, we were approached by an archaeologist who works within the circles of The British Museum.
He asked if it was possible to arrange a meeting with the landowner of one of our sites and gain permission for a full archaeological dig to take place there.
That meeting took place in November 2016 between all parties and the fundamental structure for the dig was designed. The landowner was asked where they could dig, he answered “you’re the experts, you tell me”.
With that, the dig happened and we were so proud and excited to see a full excavation happen on one of our permissions.
The equipment was craned in and the JCB arrived to cut the very first of three trenches that were assigned to cover crop marks identified during the research phase carried out earlier.
Over the week there were several different archaeologists and “volunteer diggers” on-site and each of them were amazed at the amount of finds that we had collected. They asked how long it had taken to accumulate such a large number of finds? …….. 20 months was the answer!
With that, another archaeologist asked if we were married? I replied “no, we just detect together”.
Family Days
On one of the days a “Family” session was held where all family members from 6 years upwards took part in the actual excavation and also learnt about metal-detection and the huge part it played in the excavation taking place.
The initial Trench Cutting
The JCB cut into the first 12 inches or so which was basically down into the sub-soil and 2 inches below the maximum plough depth of 10 inches.
The excavator driver very kindly spread the spoil heap out across the field surface so that we could fully explore what may have been missed on our previous surveys.
We couldn’t wait to see what may lie in the spoil heaps as this would show up any small coins such as cut-quarters or halves and other items that were obscured due to all the myriad of factors mentioned on all the metal-detecting forums since time dot.
We estimated that the initial spoil heaps consisted of 6.9mtr³ or 6,900 litres or 244 cubic feet of soil dug out by the JCB which represents the maximum detectable layer that is in range/just out of range of machines currently used on arable land.
No metallic finds whatsoever were discovered in the spoil heaps created by the JCB! Perhaps testament to the efficiency of how a carefully structured 100% coverage strategy pays dividends?
The Main Excavation
The archaeologists then started the painstaking process of trowelling back the trench base and it wasn’t long before structures and “features” started to show up.
All three trenches had differing features, some showing up as changes in soil colours and textures, others as solid evidence such as building material.
Trench 3 for instance had a collapsed wall with huge animal bones within it. The dates have yet to be determined but some great C13th to C14th pottery came up from ditch fill soil in the trench.
Trench 3 also had a ditch 5 metres wide and all trenches had other ditches intersecting each other.
The trench walls, base and spoil heaps were constantly checked for any items missed on our previous surveys. Nothing metallic was found, again showing that nothing was missed during our surveys but perhaps more importantly, nothing had “sunk” to a depth which is out or range to all detectors.
On the last day, trench 2 was scanned and two Medieval dress hooks were found, both almost identical.
One came from the ramp leading into the trench and was at a depth of 20 inches (below the plough and sub-soil), the other from a depth of 3 feet! Both items well out of range of today’s machines.
The deeper dress hook appeared to be in the ditch fill context and was deposited into an older existing ditch.
So, from a field that has produced several Medieval finds, even some Roman coins and artefacts, the only metallic finds were two dress hooks! These were beyond detecting range so we were cheating in a way!
There were no cut-quarters, cut-halves or coins such as Henry III pennies, denarii or buckles etc so obviously nothing was going to “magic” its way to within coil range as it doesn’t exist.
The fact is that 55 to 60 tonnes of carefully excavated soil didn’t produce any metallic finds.
We all know that finds in a field are finite and there will be a point were once it was justifiable to travel several miles/hours to a field, but the time will come that the field will have to be laid to rest.
Unless of course you live next door to it, then it’s always worth the time-out to have a walk around and let the magic of imagination run away with you.
As we’ve said many times, we wouldn’t travel the distances we cover just for one cut-quarter.
In addition, we had an experienced overseas visitor who had a Minelab CTX 3030 but couldn’t find anything either!
Conclusion
We have found that if a field isn’t covered 100% (as per our previous posts) targets will be missed.
Indeed, and we are just as guilty as others in not covering an area 100% as we’ve surveyed areas that it was nigh on impossible to keep an accurate track on where you are up to, due to crop alignment, or mis-alignment to be more accurate.
This may equate to a maximum 90% coverage ratio meaning that:
1,619 mtr² of the 4-acre field …..or 0.4-acres had been totally missed.
1,619 mtr² is a huge area so it’s easy to see why an unstructured search pattern will result in missed items. This is why a field that hasn’t been covered 100% “will always keep giving”, …….well up to a certain point anyway.
As we’ve seen in several other posts, some detectorists may have doubts about their abilities and their machines’ capabilities but hopefully this example may show that, on the whole, no signals equal no targets, as simple as that.
As can be seen, in the 30 cubic metres of soil removed or 30,000 litres or 1,060 cubic feet of soil (approx. 55 to 60 tonnes) that were meticulously scanned, nothing was found.
So, there were no items at all squirreled away in there somewhere that may “magically materialise” on another future visit as they didn’t exist in the first place.
Items recovered on subsequent visits to a field that has already searched have simply been missed or the target was out of range of the machines capability.
The lesson here is don’t get stressed out if you’re not finding anything, move on until you do find something! Ignore all the myths/urban legends and trust your machine, after all, it doesn’t have an imagination, it just follows fact.
There are two facts that help in successful detecting and increased confidence:
- Is there anything there at all?
- 100% coverage will give an accurate background to the history there.
Whether or not a cut-quarter is on its edge or any of the myriad of excuses as to why an object isn’t recovered only adds another layer of “myth” or uncertainty that will always exist, and add fuel to the “what if” phycology.
If you survey a field 100% and it produces one Henry III penny, it’s all down to the individual as to how much effort and expense you want to spend finding any further artefacts or coinage within that field?
Sifting through 55 to 60 tons of soil, carefully excavated from a superb Medieval site proved it for me.
Images of the excavation can be seen here.