The Types of Metals Found in English Fields: A Reflection of Human History and Pollution

For metal detecting enthusiasts, every field is a mystery waiting to be solved. Whether it's a rural pasture, a wooded area, a beach or parkland, the ground is often filled with clues to the past. But as you dig, you might also encounter a wide range of metals — some ancient, others more modern — that can tell you just as much about the history of human activity and pollution as they do about past generations.

In this blog post, we’ll explore the types of metals commonly found in English fields and how the diversity of these materials can be both eye-opening and concerning when it comes to understanding the extent of human pollution of the land.

Common Metals Found in English Fields

1. Brass

   Brass is a popular alloy of copper and zinc, and it has been used for centuries in various items like buttons, and fittings. As you scour the ground, brass artefacts can be quite common, especially in areas with a miliary connection.

Historically, brass was used in everything from jewellery to military buttons and ammunition. Today, you'll find brass relics scattered across the countryside, especially in places with long-standing agricultural use or with a link to military activity, especially from the world wars. Interestingly, brass can weather quite well in the soil, often appearing as greenish or tarnished yellowish artefacts.

From a pollution perspective, the presence of brass could indicate a period of industrial activity or trade, but it also reveals how much human-made materials have permeated the land over time. Brass, being an alloy, doesn’t corrode as quickly as other metals, meaning remnants of past generations can stay in the earth for centuries.

2. Copper

   Copper is one of the oldest metals known to humans, and it has been used for coins, tools, jewellery, and household items for millennia. Whether it's a Roman coin, an old copper button, or fragments of copper wire, detecting copper can provide fascinating insight into the history of an area.

Copper items are prone to oxidisation and, when found in the soil, will often appear as a greenish-blue patina. This corrosion is natural, but it also highlights how copper-based products have slowly leached into the environment. The presence of copper in the soil, particularly in agricultural or industrial areas, may indicate significant periods of human habitation or trade.

3. Iron

   Iron is perhaps the most commonly found metal in English fields, and it has been used since the Iron Age. Today, you'll find everything from old tools and nails to agricultural implements and even fragments of machinery. Iron doesn’t last as long in the soil as some other metals, as it rusts and corrodes more easily, leaving behind a red, rusty residue.

The abundance of iron artefacts in the ground is often a reflection of industrialisation and agricultural development. Iron nails from centuries-old houses, farming tools, and broken machinery pieces all paint a picture of an industrialised landscape. From a pollution standpoint, the large quantities of iron found in the soil indicate a long history of human activity, where iron tools and machinery were used extensively and often discarded without thought for long-term environmental impact.

4. Pewter

   Pewter, an alloy of tin with lead and other metals, was once a popular material for everything from plates and cutlery to candlesticks and buttons. While pewter is not as commonly found as iron or brass, when it is discovered, it can be quite significant in terms of the historical context it provides.

The metal is often found in the form of buttons, coins, or household items, particularly in fields near old homes or medieval sites. The use of pewter highlights the evolution of metalworking techniques and consumer goods over time. However, from an environmental standpoint, pewter's lead content can be a reminder of past practices where heavier, more toxic metals were incorporated into everyday life. Lead contamination in the soil remains a concern, particularly in older fields where heavy metals like lead have been leached into the environment.

5. Lead

   Lead has been used since ancient times, notably in pipes, weights, and even in everyday objects like buttons, toys and roofing. In fact, many old lead tokens and even pieces of lead pipe are regularly uncovered in English fields, especially in areas once used for mining or near historic towns.

Lead is particularly concerning from an environmental perspective due to its toxic properties. Over the centuries, the extensive use and improper disposal of lead items have led to widespread pollution. If you’ve ever detected in an area with a history of lead use — whether it’s near old mining regions or long-abandoned settlements — you may find lead fragments scattered across the field. Unfortunately, lead doesn’t break down naturally, meaning the contamination left behind can persist for centuries, affecting local wildlife and even the soil's health. Identifying led objects and dating them accurately can be challenging. Unless the object is marked in some way as to suggest a use and date, it could be extremely old or relatively new.

6. Aluminium

   Aluminium is a much more modern material, first widely used in the late 19th century and increasingly prevalent in the 20th century. While it might seem out of place when found in a field, aluminium items such as ring pulls, cans, and foil can be annoyingly common.

The presence of aluminium, particularly in more recently used fields, is a clear sign of human activity in the 20th and 21st centuries. Although aluminium is generally not as hazardous as lead or copper, its widespread presence speaks volumes about the increase in consumer products and disposable materials. This form of pollution is more modern but still represents a significant environmental challenge as aluminium, while recyclable, often ends up discarded in the soil due to lack of proper disposal. Aluminium is the bane of any detectorist, giving target IDs in the same range as silver on some machines. Unfortunately, you have to dig it, or risk leaving a great find in the ground.

An Eye-Opening Reflection on Human Pollution

The variety of metals you encounter while metal detecting can serve as a powerful reminder of the impact humans have had on the landscape. From ancient bronze tools to modern aluminium wrappers, every piece of metal tells a story of human habitation, trade, industry, and unfortunately, pollution.

One of the more eye-opening aspects of metal detecting is realising how much metal has been discarded or lost over time. Fields, once pristine and untouched, now bear the traces of centuries of human activity. These metals — from the centuries-old iron nails to the aluminium of the 20th century — often lie buried, unseen but ever-present.

The problem of metal pollution has, in many ways, become an ecological issue, especially in areas where certain metals like lead or copper have leached into the soil. As detectorists, we can often uncover the sheer extent of this pollution, and it serves as a reminder of the environmental legacy left behind by our predecessors. We always remove what we find and dispose of it safely if its junk.

A Call to Action for Metal Detectorists

As you dig through the soil in search of history, it’s important to keep in mind the broader picture: these artefacts are not just relics of the past, but a reminder of the challenges facing modern land management and environmental health. As responsible detectorists, it’s vital to respect the land, properly dispose of non-valuable finds (such as modern junk metals), and report any hazardous items, such as ordinance, to the relevant authorities.

In the end, metal detecting isn’t just about finding treasure — it’s also about understanding the layers of history and the environmental impact humans have had over the centuries. So, the next time you uncover a lead weight, an iron nail, or a bit of brass, take a moment to reflect on both the story it tells and the legacy it leaves behind.