How many questions are in this quiz?

This quiz has 109 questions focused on doubled dies and off-center U.S. coin errors.

What format is the quiz in?

Each question is multiple-choice with 4 options, and there’s no timer so you can take your time.

Is this quiz only about doubled dies?

No. It covers doubled dies and off-center strikes, including how to tell them apart from common look-alikes.

How do difficulty and question count work?

You can choose how many questions to answer and select a difficulty level; mixed difficulty includes both easy diagnostics and subtle cases.

What mistakes does this quiz help prevent?

It targets common misidentifications like machine doubling, wear, and damage being mistaken for true mint errors.

U.S. coin errors Quiz

About this quiz

What you’ll practice

Doubled dies and off-center strikes can look obvious in photos, but tricky in hand—this quiz helps you build a repeatable checklist for what to examine first. You’ll review key diagnostics like notching, split serifs, design doubling patterns, and how off-center percentages affect what’s visible.

Every question uses a 4-option multiple-choice format with no timer, so you can slow down and focus on the details that matter.

Common pitfalls to avoid

Many “errors” are really post-mint damage or machine doubling, and this quiz highlights the clues that give them away. You’ll also see how lighting, wear, and low-resolution images can hide or exaggerate doubling.

Confusing machine doubling with true doubled-die hub doubling
Overvaluing minor off-centers that don’t show a date or design focal point
Missing directionality (spread) and consistent doubling across devices
Ignoring strike weakness and wear that can mimic doubling
Assuming any doubled letter equals a valuable variety

Difficulty and settings

Difficulty is mixed by design: easier items focus on big, unmistakable diagnostics, while harder ones include subtle doubling, borderline off-centers, and look-alike damage. Before you start, pick how many questions you want to answer and set the difficulty to match your comfort level—short sessions for quick drills, longer runs for full practice.

Use your results to target weak spots, then replay with a higher difficulty to sharpen your attribution skills.