Coin Grading Standards: From FDC to Proof and the Sheldon Scale

When you start buying coins, whether it concerns pure investment gold or rare collectibles, terms fly around your ears. What is the difference between Proof and Prooflike? Why is an FDC coin more expensive than a UNC example? And what does a score of MS-70 mean on a certified coin?

The quality of a coin is, alongside the gold or silver price and rarity, the most important factor determining its value.

In this article, we explain exactly what the different quality standards for coins mean, how the international Sheldon scale works, and what you as an investor should look out for when inspecting a coin.

The different quality types explained

In numismatics and the world of precious metals, we make a strict distinction between coins intended for circulation (or bullion trade) and coins specially minted for collectors.

The price is often determined not just by the weight in gold or silver, but precisely by the quality of the strike.

Below you will find the definitions of the most common qualities, ranked from low to high.

1. Circulation quality (Bullion)

These are coins minted to serve as legal tender or traded purely for their metal value.

• The production process: These coins are minted in huge numbers and at high speed. After striking, they fall into a large collection bin. As a result, the coins collide with each other, which can lead to small scratches, dents, or contact marks (bag marks).
• For the buyer: Examples are the standard Krugerrand, Maple Leaf, or Philharmonic. For investors in physical precious metals, this is the standard quality: you pay for the weight in pure gold or silver, not for the aesthetic perfection of the coin.

2. Uncirculated (UNC)

A coin is Uncirculated if it has left the coin press and has never circulated in payment traffic.

• Characteristics: The coin still possesses its full, original 'mint luster'. There is no wear from hands or wallets.
• Nuance: Because UNC coins are also often mass-produced (just like circulation coins), small damages from the production process (the fall into the bin) may be present. UNC is therefore a state of preservation, and not necessarily a special, high-quality striking technique.

3. Brilliant Uncirculated (BU): better finish than UNC

This is a quality step higher than the standard UNC. BU coins are minted with new, polished dies.

• Characteristics: The coins shine more strongly and often have sharper details than standard UNC coins. The surface is more even.
• Production: BU coins are treated with more care. After minting, they are not dumped into a large bin but are often placed directly into a tube or blister pack to minimize contact marks. Many collectors see BU as the perfect entry-level quality: more beautiful than bullion, but cheaper than Proof.

4. Fleur de Coin (FDC)

The term Fleur de Coin (literally: flower of the coin) is mainly a concept in the Netherlands and Europe. It indicates the absolute highest achievable quality for a circulation coin.

• The definition: The coin is perfectly minted, has its full original matte luster, and shows, even under a loupe, absolutely no damage. The dies were fresh, and the coin has been treated with care.
• Note: Sometimes FDC is also used by mints as a marketing term for special annual sets that are minted one by one. A 'real' FDC coin is simply flawless in the eyes of the purist.

5. Prooflike: what does it mean?

As the name suggests: these coins look like Proof coins, but are not quite there.

• Appearance: The coin has mirrored fields (the background), making the relief pop out beautifully.
• The difference: With Prooflike, often only the dies are polished and not the planchets themselves. Also, they are minted at normal speed. As a result, the contrast between the mirrored background and the matte relief (frosted effect) is less sharp than with a real Proof coin. It is a beautiful middle ground for collectors.

6. Proof (PP - Polierte Platte): highest quality coins

Proof is the very highest quality a mint can produce. Important to know: Proof is not a state of preservation, but a special minting technique for, among other things, collector coins.

• The process: Both the planchets and the dies are individually polished before minting. The planchets are placed into the press by hand (with gloves). Subsequently, the coin is struck multiple times with the die.
• The result: An extremely sharp relief with a deeply mirrored background and a matte, whitish portrait (cameo effect).
• Vulnerability: Proof coins are very fragile. A single fingerprint can permanently damage the mirrored layer. They are therefore always supplied in a protective capsule and should essentially never be taken out of it.

A Proof coin is the highest quality coin you can buy.

The Sheldon Scale: the international standard for coin quality

While in the Netherlands we often use terms like 'Zeer Fraai' or 'FDC', the international trade (and especially the American market) uses the Sheldon scale. This measurement system was developed in 1949 by Dr. William Sheldon and has since become the global standard for grading coins.

The scale runs from 1 to 70, where 70 stands for absolute perfection. For investors and collectors dealing in certified coins (in so-called 'slabs' from PCGS or NGC), knowledge of these numbers is essential. A small difference in the number, for example between an MS-64 and an MS-65, can mean a huge difference in value.

The most important distinction on the scale lies at the number 60. Everything below 60 has traces of wear (circulation). Everything from 60 and higher is uncirculated (Mint State).

Table: the Sheldon scale translated

Below you can see how the international numbers relate to the Dutch terms.

Note: for normal coins, the abbreviation MS (Mint State) is used. For Proof coins, PF or PR is often used (e.g., PF-70).

Judging coin quality yourself: what should you look for?

Do you want to make an estimation of the quality of your coin yourself? You don't have to be an expert to recognize the first signs of wear. Grab a good loupe (preferably 5x or 10x magnification) and ensure bright, direct light.

Pay specific attention to the following three points during your inspection, as wear is often visible here first:

1. The 'high' parts of the design

Wear always starts on the parts of the coin that protrude the most. With portraits of kings or queens (such as on the Dutch Gold Ten Guilder), these are often the locks of hair, the cheek, or the crown.

• The test: Tilt the coin in the light. Do you see a dull, gray spot on these high points while the rest shines? That is friction. If these details are faded and merge into each other, the coin is no longer 'FDC' or 'About Uncirculated', but rather 'Very Fine'.

2. The rims and the edge

Examine the rim of the coin critically. Are there small pits, dents, or chips visible on the rim? This indicates that the coin has fallen at some point or bumped hard against other coins in a cash drawer or wallet.

• The impact: A coin may shine beautifully, but a significant hit on the rim (a rim nick) immediately brings down the quality score and the value for collectors.

3. The fields (the background)

Look at the flat, open parts of the coin surrounding the portrait or coat of arms.

• The test: Are these fields mirrored and smooth? Or do you see countless small scratches running crisscross through each other (hairlines) under the loupe? Many scratches indicate cleaning or rough handling. A perfect coin has 'calm' fields without distracting lines.

Tip: polishing dirty coins? In this article, you can read how best to clean your coins.

The Sheldon-scale is used to grade coins. MS-70 is the highest score possible, for a perfect coin.

Grading services: what are PCGS and NGC?

With valuable and rare coins, it is sometimes difficult to determine the quality exactly yourself. The difference between a coin that is just not quite perfect (MS-69) and a coin that is absolutely perfect (MS-70) is barely visible to the naked eye. Yet this difference in quality can be worth hundreds, if not thousands of euros in the trade.

To prevent discussion between buyer and seller, there are independent assessment companies, the so-called third-party grading services. The two largest and most respected players worldwide are:

• PCGS (Professional Coin Grading Service)
• NGC (Numismatic Guaranty Company)

How does the process work?

When a coin is sent to one of these services, it is assessed by multiple anonymous experts. They look at two things:

• Authenticity: is the coin real and not counterfeit?
• Quality: what is the exact score on the Sheldon scale (1 to 70)?

After the assessment, the coin is hermetically sealed in a hard, transparent plastic holder. In the collecting world, we call this a 'slab'.

The advantages of a 'slab'

The holder features a unique serial number (which can be checked online), the established quality, and a barcode. For you as a buyer or seller, this offers major benefits:

• Certainty: you know 100% sure that the coin is real.
• No discussion: the quality has been established by an independent third party. A coin with an MS-70 score is globally recognized as perfect.
• Protection: the hard plastic holder protects the coin against drops, scratches, and fingerprints.
• Tradability: 'slabbed' coins from PCGS or NGC are internationally very popular and often easier to trade than loose coins because the buyer knows exactly what they are buying.

Investment coins vs. collector coins: for whom is the quality standard important?

Should you, as a gold investor, worry about these quality standards? That depends entirely on your goal. In the world of precious metals, we distinguish between two markets:

1. The investor (bullion)

Are you buying purely for the physical metal value (gold or silver) to protect your wealth? Then bullion or circulation quality is sufficient.

• The focus: You pay the lowest premium on top of the current gold price.
• The quality: A small scratch on a Krugerrand or Maple Leaf does not make it worth less in gold weight. As long as the weight and purity are correct, the coin is tradable.

2. The collector (numismatics)

Are you looking for historical or collectible value in addition to the metal value? Then quality is all-determining. Here it pays to look for BU, proof, or certified examples.

• The focus: You often pay a higher premium for rarity and perfection.
• The quality: A collecting coin of the same vintage can be worth €500 in 'Very Fine' quality, but as much as €5,000 in absolute top quality (FDC).

Note: more than just quality

The total value of a collector coin is determined by a combination of four factors. Quality is just one of them:

• Quality: the more flawless the coin, the higher the value.
• Mintage: how many copies were originally minted?
• Scarcity: how many are left now? (Many coins have been melted down over time).
• Demand: is the country, the theme, or the period popular with collectors?

A coin of 'only' very fine quality can therefore sometimes be more valuable than an FDC coin of which millions were made.

Conclusion: knowledge of quality standards means ROI

Whether you invest in physical gold for wealth preservation or are building a rare numismatic collection: knowledge of quality is important. The distinction between a circulation coin and a perfect Proof strike directly determines the value and future tradability of your purchase.

Use the Sheldon scale as your guide and be critical of details. At The Silver Mountain, you are assured of transparency. All our coins are strictly checked so that you know exactly what you are buying: from affordable bullion to certified top quality.