20-Year Coin Price Rally Decoded: Why Condition, Rarity & Third-Party Grading Drive Markets

Coin Prices Have Soared in the Last 20 Years as Third-Party Grading Changed Market Rules

On June 12, 2023, British coin dealer Baldwin's published its perspective on the significant rise in coin prices over the past two decades and the impact of third-party grading services (TPGs) on the market.

Factors cited for the price increases include an unstable economy, low interest rates, and a lack of trust in banks. Rare coins in exceptionally fine condition have seen particularly sharp appreciation. This trend has been bolstered by third-party grading. Demand for objective, third-party condition assessment grew, especially during the pandemic when buyers could not inspect coins in person.

The author points out that while third-party grading has fundamentally changed the market and led to record-breaking prices, it has also had the effect of destroying the value of some of the highest-quality coins. This analysis examines the pros and cons through three coins that differ in condition, rarity, and the impact of third-party grading.

A Success Story: The Top-Graded George II Guinea Graded PF65 by NGC

The first case is a 1729 George II Proof Guinea, graded PF65 by NGC. This coin is presented as a classic example where the three key factors—condition, rarity, and third-party grading—all worked in its favor.

* Condition: As a proof coin, it maintains exceptionally high quality, featuring mirrored fields and an unworn design. * Rarity: It is classified as R4 (11-20 known), but evidence suggests it may be even rarer. Over the last 20 years, the only comparable auction record is for an inferior PF64 specimen that sold for £45,600 in 2017. * Third-Party Grading: The PF65 grade is the highest awarded to any known example, and given its rarity, it is considered unlikely that a higher-graded specimen will emerge.

For these reasons, the coin is a perfect option for investors and collectors. Considering current market trends, its value is estimated to be close to £100,000.

The Carlisle Siege Coin: Historical Value Not Reflected in Price, Receiving No Benefit from Grading

The second case is a three-shilling silver coin struck during the Siege of Carlisle in 1645 amid the English Civil War. This coin is highlighted as an example of a piece with great historical importance that does not benefit from third-party grading.

* Condition: Struck hastily during a siege from melted-down silverware, no high-grade examples exist. The piece shown has a crude strike but the date and denomination (III) are visible, making its condition typical for the type. * Rarity: It is extremely rare, with fewer than 10 known to exist. * Third-Party Grading: Due to its original low strike quality, it would not receive a high numerical grade if submitted for authentication. There is little incentive for grading, and as a result, its value has not risen significantly in the past 20 years. While its historical context ensures constant demand, it is said to be undervalued in a market dominated by third-party grading.

A Minor Scratch Leads to "No Grade": The Value Barrier Faced by the First Gold Sovereign

The third case is the first-ever gold Sovereign, minted during the reign of Henry VII. This coin highlights the problem of how a minor flaw can cause third-party grading to dramatically reduce a coin's value.

* Condition: This example has an unusually sharp strike for a gold coin of this period. The King's portrait is clear, and it is considered one of the finest surviving specimens. However, it has a very minor scratch, only visible upon close inspection. * Rarity: As the first-ever Sovereign, mintage was limited. Few have survived, and many of those are poorly struck. * Third-Party Grading: Because of this minor scratch, the coin would likely not receive a numerical grade and instead be designated "Details."

The 2023 catalog price for this coin in VF (Very Fine) condition is £165,000. In 2010, a similar, undamaged specimen sold for £186,000. While that coin would be estimated to be worth over £300,000 today, this scratched example is described as being worth "about half that price," a substantial decrease.

The Grading System's Distortion: How even slight issues now destroy the value of many top quality coins

The author identifies the assessment of coins with minor flaws as the biggest problem with third-party grading. Twenty years ago, if a top-quality five-guinea gold coin had a minor scratch, its price might have been reduced slightly, from £10,000 to £9,000. Despite the scratch, if it was visually appealing, it was still considered one of the finest examples.

In today's market, however, an undamaged coin might be graded "MS63" (estimated at £150,000–£200,000), while one with a minor scratch receives "Unc Details" (estimated at £30,000–£40,000), creating an astronomical price difference. It is argued that this price gap is unjust and does not reflect the coin's inherent rarity or beauty.

To solve this problem, the author suggests alternatives. For example, assigning a lower numerical grade based on the flaw's severity, or using a notation like "AU58 light scratches" that indicates both the underlying grade and the issue. The conclusion is that the current situation, where rare coins are drastically undervalued for minor imperfections, should be corrected through such revisions.