Stamp collecting is more enjoyable when you can build your skills one small, manageable step at a time. Many collectors—new and experienced—tell us the same thing: they want to learn more, but they don’t want long lectures, complicated instructions, or information overload. The Stamp Skills Series was created to address those concerns. Much of the material in this series is kept at an elementary level so collectors of all experience levels can follow along comfortably.
This series breaks each topic into four short, practical steps, with a step released by the next club meeting (1st & 3rd Thursdays of the month). Each step focuses on one specific skill you can try immediately, using the stamps and tools you already have.
After Step 4, the topic is considered complete. At that point:
The full four‑step topic is moved into the New Topics section under Educational Topics and eventually moved to the Explore Past Topics on the website.
You can view or review previous steps for this skill by clicking Previous Steps
The next topic in the series begins with Step 1.
This series is being introduced as a "Pilot Program" in our Educational Topics . We encourage you to provide feedback to help guide future improvements.
Please use the feedback form at the bottom of this page and let us know your thoughts.
Progress 🟦🟦🟦⬜ — Step 3 of 4
Beginner Skill: Measuring Perforations and Understanding What Differences Mean. Only round hole perforations are discussed in this skill set. See Stamp Perforations under Past Topics under Educational Topics for a discussion on other types of perforations.
Click here to see Perforation Diagram
Skill: Identifying Valuable Differences
What you do
Compare your stamp with others from the same country or series.
Measure each one.
Look for differences in perforations or margins.
What the results mean
Top/bottom one number, left/right another — all clean and even
→ Intended variety (compound perforation).--------------------------------------------------------------->
One side has NO holes
→ Error (imperf or imperf‑between).
Margins unusually wide
→ Error or variety.
What to do next
Clean differences → mark as possible variety.
Smooth edge → mark as possible error.
Messy differences → treat as possible alterations.
Try it now
Check a set of stamps from the same series.
Does one measure differently?
Does one have a smooth edge?
⭐ Example: The Compound Perf Surprise
A collector found a stamp with perf 11 on top and perf 10 on the sides — a legitimate compound variety.
⭐ Practical Tip
“Clean differences = variety. Missing holes = error. Messy differences = alteration.”
1. APS – “Stamp Collecting 101: Handling Stamps”
2. Smithsonian National Postal Museum – “Caring for Your Stamps and Covers”
3. APS – “How to Store Your Stamps” & Beginner Guides on Perforations
Progress 🟦🟦🟦⬜ — Step 3 of 4
Thank you for visiting Stamp Skills. The next step or skill will be presented by the next club meeting (1st & 3rd Thursdays of the month).