A metal detector is primarily designed to find metal objects. The most of the time, that’s exactly what you will find (think about things like jewelry, money and artifacts). However, there are situations where your metal detector may detect something different than metal objects, such as pottery shards.
This may seem illogical, as pottery theoretically should not be detectable by a metal detector. So…
…Why does my metal detector detect pottery?
A metal detector can sometimes pick up pottery because some types of pottery contain minerals or metal components like iron and lead that are detectable by the metal detector. These minerals and metal components can often be found in the clay or in the added metallic paint or glaze of the pottery.
While many people believe that discovering pottery with a metal detector is negative thing, it is actually a positive indicator. In this blog, I will explain you the benefits of finding pottery with a metal detector. Additionally, I will tell you why metal detectors are able to detect pottery and I will also give you tips how to avoid finding it. Enjoy Reading!
Understanding the composition of pottery
In order to understand why certain types of pottery can be detected by a hobby metal detector, it is important to have knowledge of the main components that make up pottery.
The main ingredient of pottery is clay, which is a mixture of minerals including silica, alumina and water. These kind of minerals can contain small amounts of metallic elements. This means that these minerals will be picked up by a metal detector when the concentration is high enough. This, in turn, means that some types of pottery will set off a metal detector.
Of course, the concentration of these minerals must be high enough. Furthermore, large pottery objects are more likely to be found than small pottery objects. Another factor that determines whether your metal detector will pick up pottery or not are the settings of your metal detector.
If you are using a relatively high sensitivity level it will be more likely that your metal detector finds pottery. Additionally, when you don’t properly use the discrimination function and the ground balance function, you will sooner find pottery.
Later in this blog I will tell you how you can use these settings to avoid finding pottery.
The role of paints, glazes and other embellishments in pottery detection
In addition to the composition of pottery (clay), there is another reason why your metal detector may detect pottery. This reason is the decoration of the pottery.
Much pottery is decorated with paints, glazes or other embellishments like brass inlay, metal handles, metal rivets, luster, gold leaf or metal stamps. These kind of (metal) decorations can be picked up by a metal detector.
So if you see some decoration on the pottery you found with your metal detector, you might already found out the reason why your metal detector picked it up.
What kind of pottery can be found with a metal detector?
A metal detector will be able to detect pottery that is made of materials that contain metal oxides or other conductive substances. Some really common types of pottery that can be found with a metal detector are therefore; Roman pottery, Medieval pottery and Early Modern pottery.
Let’s start with the Roman pottery. This type of pottery often contains metal such as copper, lead and iron. Examples of Roman pottery that contains metal are Samian Ware (made of red clay), Amphora (lead in their glaze) and Terra Sigillata (glossy red surface).
Besides finding Roman pottery, you will also be able to find some cool Medieval pottery. This type of pottery often contains iron. Some examples of Medieval pottery are Islamic Lusterware, German Stoneware and Maiolica pottery.
Some examples of pottery from the Early Modern Period were Faience pottery, Dutch Delftware and Chinese porcelain. The most of this pottery was decorated with metallic pigments like iron.
Why is finding pottery such a good thing in metal detecting?
Many people don’t like to find pottery with their metal detector because they think it is pointless. However, the opposite is true; pottery is a fantastic clue to other cool stuff that you can find with a metal detector. Let me explain this to you.
When you find pottery, you know that you are metal detecting at the right place. The reason for this is because pottery is often found at locations where people have gathered back in the days. This means that there is a high chance of finding other lost stuff like coins, thimbles, jewelry and artifacts.
So the next time you find pottery, please don’t be grumpy, but smile instead. Finding pottery is a good sign that you are on the right track!
What kind of sound does a metal detector produce when it detects pottery?
You may want to know what kind of sound your metal detector produces when it detects pottery. By knowing the sound of the target, you can take this into account if you want to find potsherds for example.
Your metal detector will likely produce less intense sounds than when detecting large and highly-conductive targets since the metal embellishments on pottery are often very small. As a result, the beeps produced by your metal detector will be weak, low and inconsistent when detecting the metal fragments of pottery.
How do I avoid finding pottery in areas with a lot of pottery fragments?
Maybe you don’t want to find pottery with a metal detector at all. After all, the purpose of metal detecting is to find valuable metal targets, not pottery.
If you want to avoid finding pottery with a metal detector you should lower the sensitivity level of the metal detector. Furthermore, you should discriminate the type of metals that are used in pottery. You should also research the site you plan to explore.
The disadvantage of lowering the sensitivity level is that your maximum detection depth will decrease which can lead to missing targets. Therefore, find the correct sensitivity level. With the discrimination function you can choose to ignore certain metals.
Therefore, you should discriminate the metals that are often found in pottery. These metals are often iron, lead and copper. In my other blog, you can read how you should use this discrimination function.
Last but not least, it is good to do some research in advance. Get to know the spots where many pottery has been found before. If you want to avoid finding pottery, you should also avoid these spots.
Frequently Asked Questions
Yes, pottery found with a metal detector can definitely be worth some money. The amount of money depends on factors such as age, condition, rarity and historical significance. Potsherds are often worth less than pottery that is still intact. If you want to know the exact value of the pottery you found, I would recommend you to go to an experienced appraiser.
It can be really difficult to identify pottery you found. You can try to look for clues or text on the pottery and Google it. However, it is definitely the most easiest to go to an appraiser or other person that has a lot of knowledge about history and pottery.
There are many different types of metals that can be found in pottery. The most common metals are iron, lead, copper, tin and silver. You will often find these metals in the clay or in the glaze of the pottery.
This depends on the laws and regulations in the area you found the pottery. Very often, the found pottery could be part of a larger archaeological find which means that you have to handle it to your local authorities for further investigation. Therefore, I would recommend you to check the laws and rules of your local authorities.