MS-66 is a grade on the Sheldon Coin Grading Scale, which evaluates the condition and quality of coins. It reflects a nearly flawless coin with superior luster, sharp detail, and minimal imperfections. Understanding adjectival conditions and numerical grades of coin grading, the Sheldon scale, and the implications of such a grade in the world of coin collecting and investing.
The Sheldon Scale was developed in 1949 by Dr. William H. Sheldon. It was originally used to grade large cents minted between 1793 and 1814. It ranges from 1 to 70, with 1 being used for barely identifiable coins and 70 representing a flawless coin with no wear whatsoever. The Sheldon Coin Grading Scale has been adopted for grading all U.S. coins and has become the industry standard.
The scale is divided into several categories:
- Poor (P-1) to About Good (AG-3)
- Good (G-4 to G-6)
- Very Good (VG-8 to VG-10)
- Fine (F-12 to F-15)
- Very Fine (VF-20 to VF-35)
- Extremely Fine (EF or XF-40 to XF-45)
- About Uncirculated (AU-50 to AU-58)
- Mint State (MS-60 to MS-70)
Understanding MS-66
An MS-66 coin is considered to be in Mint State condition, which refers to coins that have never been in circulation and show little to no signs of wear. Mint State coins, or MS coins, are nearly flawless to the naked eye but may have very minor imperfections visible under magnification. Here’s a breakdown of what MS-66 typically entails:
- Luster: The coin exhibits full, original mint luster. This is the shiny, reflective quality that comes from freshly minted coins.
- Strike: The coin is well-struck, meaning the design details are sharp and clear.
- Eye Appeal: Eye appeal assesses a coin’s visual attractiveness with good color and minimal distractions.
- Marks: There may be a few minor contact marks or hairlines, but they are not in focal areas and do not detract significantly from the coin’s appearance.
A key distinction between MS-66 and its neighboring grades lies largely in the subtleties. Compared to an MS-65 coin, which may have slightly more noticeable contact marks or a weaker strike, MS-66 coins show superior preservation and eye appeal. On the other hand, MS-67 coins often exhibit near-pristine surfaces, even stronger luster, and almost imperceptible imperfections. The threshold from MS-66 to MS-67 is particularly competitive, hinging on advanced criteria like strike sharpness and luster uniformity,
Coin grading at this level and other mid-points between adjectival grades involves a degree of subjectivity. Two coins of the same date and mint may receive different grades based on slight differences in eye appeal, mark placement, or how a grader interprets luster and strike. Even experienced graders may differ on whether a coin is a strong MS-65 or a low-end MS-66. This is why coin grading organizations always have multiple graders working and why certified coins from trusted grading services carry such weight in the market.
Who Assigns MS-66 Grades?
Professional third-party grading services typically perform coin grading. Some of the reputable organizations include:
- PCGS (Professional Coin Grading Service)
- NGC (Numismatic Guaranty Company)
- ANACS (American Numismatic Association Certification Service)
- CACG (Certified Acceptance Corporation Grading)
These organizations employ expert graders who evaluate coins under controlled conditions using magnification and standardized criteria. Once graded, the coin is encapsulated in a tamper-evident holder, often referred to as a “slab,” with the grade clearly labeled.
Overview of the Grading Services
| Grading Service | Founded | Known For |
| ANACS | 1972 | Oldest U.S. grading service; known for variety attribution and problem coin grading |
| PCGS | 1986 | Market leader; strict grading standards; high resale value |
| NGC | 1987 | Global reach; consistent grading; popular with collectors |
| CACG | 2023 | Focus on premium quality coins; evolved from CAC stickering |
Grading Philosophy and MS-66 Standards
PCGS (Professional Coin Grading Service)
- Philosophy: Conservative grading, especially at higher Mint State levels. Emphasis on strike, luster, and eye appeal.
- MS-66 Traits: Strong luster, above-average strike, minor contact marks in non-focal areas, excellent eye appeal.
NGC (Numismatic Guaranty Company)
- Philosophy: Slightly more liberal than PCGS but consistent overall.
- MS-66 Traits: Similar to PCGS, allowing an unstated number of visible marks if overall eye appeal and luster are strong.
ANACS (American Numismatic Association Certification Service)
- Philosophy: Variety-friendly and more lenient than PCGS/NGC.
- MS-66 Traits: May permit more marks or slightly weaker strikes. Eye appeal matters but is not weighted as heavily.
CACG (Certified Acceptance Corporation Grading)
- Philosophy: Evolved from CAC’s premium sticker system. Focus on elite coins only.
- MS-66 Traits: CACG’s standards are typically more rigorous than those of other grading organizations. Their MS-66 standards require a well-struck design with good luster. Some scattered imperfections are allowed, but only if they are not in the focal areas of the design.
As far as rare coin grades are concerned, MS-66 is a respected grade. It represents an uncirculated, visually appealing, and nearly flawless coin that offers a blend of quality and value.
