An important factor in determining the value of any coin is the condition it’s in. Has it seen much circulation? Is it well-struck? This is something that is quantified in a “grade.”
Coin Collecting
Basics of Grading Britannia Gold Coin 1987
How to Grade Circulated Coins - Introduction to Coin Grading
Coin Collecting Blog, ANA Coin Press
Professional Coin Grading Service - Wikipedia
What Types of Coins are Good for New Collectors? - APMEX
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PCGS The Standard For The Rare Coin Industry, 53% OFF
A Comprehensive 5-Step Guide to Submitting Coins for PCGS Grading - Silverpicker
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