The structure of a coin—from the obverse and reverse to the edge

A coin is much more than a means of payment. For collectors and numismatists, it is primarily a work of art, a carrier of history, and an object of precise analysis. In this article, we present the key elements of coin construction, discussing both their practical and aesthetic functions.

Table of contents

• What goes into making a collector coin?
• Obverse – the coin's calling card
• Reverse side – information and aesthetics
• Legend – a caption that says it all
• Relief and field – details that matter
• Rim and bead – functionality and protection
• Mint mark – manufacturer's signature
• Other aspects worth knowing
• Tip for beginners

What goes into making a collector coin?

Every coin, regardless of its age and origin, has distinctive design elements that give it a unique identity.

• Obverse – the main side of a coin. From a numismatic point of view, this is the side bearing the main motif identifying the issuer, e.g., a portrait of a ruler, a national coat of arms, or an emblem.
• Reverse – the opposite side to the obverse. It usually features the denomination and thematic, historical, or decorative motifs.
• Edge – the side surface of a coin, which may be smooth, serrated (grooved), ornamented, or contain inscriptions.
• Edge – a raised rim (border) on the obverse and reverse, whose main function is to protect the coin's design from wear.
• Legend – all inscriptions on the coin, specifying, among other things, the name of the country, the ruler, the denomination, the year of issue, and the motto.
• Mint mark – a discreet symbol (letter, coat of arms, or graphic symbol) identifying the place where the coin was minted.
• Relief and field – relief refers to all raised elements of the design (portraits, numbers, letters), while the field is the smooth, flat background of the coin.

All these components play an important role—aesthetic, informational, and protective against counterfeiting.

Obverse – the coin's calling card

In the early days of coinage, the obverse primarily featured symbols of power – portraits of rulers, images of gods, or coats of arms. It was this side that served as a guarantee from the issuer and confirmed the authenticity and weight of the metal.

The most important features of the obverse are:

• portrait or symbol of state authority (coat of arms, emblem),
• often the name of the issuing country,
• high quality of detail, demonstrating the skill of the engraver,
• identifying elements for a given period or country.

Thanks to advanced minting techniques, the obverses of old coins still impress with their precision of workmanship.

Reverse side – information and aesthetics

The reverse complements the obverse, often serving an informational and artistic function. It features:

• denomination of a coin,
• thematic motifs (e.g., anniversaries, characters, flora and fauna, monuments),
• exergue – a separate, lower part of the field, where the date of issue or mint mark is often placed,
• additional markings indicating the series or variant of the coin.

Minor differences on the reverse (or obverse), such as a different arrangement of letters or details in the design, are often the basis for distinguishing variants in numismatic catalogs, which is of great importance to collectors.

Legend – a caption that says it all

The legend on the coin may be placed around the field (rim) or centrally. It has three key functions:

• identifies the country and issuer (e.g., REPUBLIC OF POLAND),
• indicates the face value (e.g., 10 ZLOTYS),
• protects against counterfeiting, as it is difficult to forge accurately.

Contemporary legends often combine artistic value with functionality, becoming one of the distinguishing features of a given minting project.

Relief and field – details that matter

• Relief is a raised design on a coin – it makes it easier to recognize the denomination, figures, and symbols, even by touch. The height and detail of the relief indicate the quality of the mint die.
• The field is the background on which the relief is located – its smoothness (often mirror-like in collector coins) or specific texture affects its aesthetic value and provides additional security.

Both the relief and the field play an important role in the process of identifying and assessing the condition of coins. The smallest scratches on the field are immediately visible and affect the numismatic assessment.

Rim and bead – functionality and protection

• The edge is the outer, lateral edge of a coin. Its design is an important security feature. In the past, serrations or inscriptions on the edge were intended to prevent the edges of precious metal coins from being cut off. The edge can be:
• smooth,
• serrated (grooved),
• with an inscription (e.g., "SALUS REIPUBLICAE SUPREMA LEX"),
• ornamented.
• The edge is the slightly raised part on both sides of the coin. Its primary function is to protect the relief from wear when the coin is lying on a flat surface.

The appearance of these elements is a feature of the coin's design and does not depend directly on the metal used in its production.

Mint mark – manufacturer's signature

The mint mark is a symbol indicating where a coin was minted. It usually takes the form of a letter, monogram, or miniature graphic symbol.

Why is it important?

• Identifies the source of the emission (e.g., the Polish Mint logo under the eagle's talon).
• It helps in dating and classifying coins (different mints could mint the same coinsin a single year).
• It increases credibility and is a key element for collectors specializing in specific mints.

Modern mints use marks as one of the elements confirming the authenticity of circulation and collector coins.

Other aspects worth knowing

• Types of coins according to their purpose:
• circulating (coin, small change) – for everyday transactions,
• collectible – from limited editions, often minted with a mirror stamp, of high artistic value,
• investment (bullion) coins – minted from precious metals (gold, silver, platinum), their value depends mainly on the current price of the metal.
• Types of coins based on their structure:
• monometallic – made of a single metal or alloy,
• bimetallic – composed of two different metals (e.g., 1, 2, and 5 euro coins).
• Basic numismatist tools:
• numismatic magnifying glass (for evaluating details),
• jewelry scale (for weight verification),
• caliper (for measuring diameter and thickness),
• neodymium magnet (for checking the magnetic properties of the alloy).

Understanding the structure of coins is the first step towards conscious collecting. It makes it easier to appreciate both the artistic and historical value of numismatic items, from the simple denarii of Mieszko I to complex contemporary issues. Although digital payments dominate today, numismatics still attracts enthusiasts, allowing them to combine the past with a modern approach to history and investment.

Tip for beginners

Before you start building your collection, it is worth deciding on its theme, setting a budget, and familiarizing yourself with basic numismatic literature. Also, remember the golden rule: never clean coins yourself, as this almost always leads to damage to their surface and loss of value. Every coin tells a story – it is worth learning about it before it goes into your album.