Grading and Authentication
Grading is the process of evaluating a stamp’s physical condition, while authentication verifies its genuineness. Together, they help determine a stamp’s market value and historical integrity. Grading considers factors like centering, perforation quality, gum condition, color freshness, and absence of faults. Authentication involves expert analysis to detect forgeries, repairs, regumming, or alterations—especially important for rare or high-value items.
Professional expertizing services offer certificates that confirm a stamp’s authenticity and grade. These services use magnification, ultraviolet light, watermark detection, and historical comparison to assess stamps. Some collectors learn to grade and authenticate themselves, developing a trained eye through experience and reference materials. Others rely on third-party services for peace of mind and resale credibility.
Stamp grading evaluates a stamp’s condition and centering, while authentication confirms its genuineness. Together, they determine market value and collector confidence.
Here’s a detailed breakdown of both processes, including standards, tools, and expert services:
Authentication ensures a stamp is not a forgery, reprint, or altered item. It involves:
Expertizing Services:
APEX (American Philatelic Expertizing Service): Offers opinions on paper, watermark, gum, cancel, and hidden flaws.
PSAG (Philatelic Stamp Authentication and Grading, Inc.): Specializes in U.S. and Canadian stamps.
ASG (Authenticated Stamp Guaranty): Provides certification and tamper-proof holders.
Techniques Used:
Ultraviolet light for paper and ink analysis
Microscopy for perforation and printing details
Watermark detection
Comparison with reference archives
Why Authenticate:
To avoid financial loss
For resale or insurance
To confirm historical or philatelic significance
Stamp grading evaluates physical attributes and assigns a numerical or descriptive score.
Centering: Alignment of design within perforations; well-centered = higher grade
Margins: Width and evenness around the design
Color: Vibrancy and accuracy of ink
Gum: Condition of adhesive on mint stamps
Perforations: Completeness and uniformity
Soundness: Absence of faults (tears, thins, creases)
Gem 100: Perfect centering, flawless condition
Superb 98: Near-perfect centering, minimal flaws
VF-XF 85–90: Very fine to extremely fine centering
F-VF 75–80: Slightly off-center, minor flaws
Average 50–70: Noticeable faults or poor centering
Grading is often combined with authentication for certified sales and auctions.
PSE Grading Guide PDF offers visual examples and centering scales
ASG Certification Lookup verifies graded stamps
APS Authentication Services explains expertizing criteria