They are all coins, they are all shiny, and they live in three completely different universes. Confusing them is the most expensive mix-up in the hobby.
Walk through any coin marketing and you will meet three species wearing similar costumes: classic coins that once circulated as money, bullion coins struck for their metal, and commemoratives struck for collectors. Knowing which is which changes how you read every price you will ever see.
A Morgan dollar or a pre-1933 double eagle was made to be spent, and was. It rode in pockets, crossed counters, sat in bank bags, and dodged the melting pot. Its surviving population is fixed, its condition census is an accident of history, and its value flows from rarity, condition, demand, and story. Nobody can make more.
An American Silver Eagle or Gold Maple Leaf is modern refined metal in sovereign uniform: struck by the millions, guaranteed for weight and purity, priced from spot plus a premium. Superb at its job, which is being metal you can trust at a glance, and its job is not rarity.
Modern commemoratives are struck by mints specifically for collectors, sold at issue prices above metal value, and, this is the key, they never circulate. Nearly every one ever sold went straight from mint capsule to display case, which means pristine condition is not an achievement; it is the factory setting. They can be beautiful and meaningful. What they are not, in almost every case, is rare in top condition, and the aftermarket has documented for decades that many trade below their original issue prices once the marketing ends.
Ask one question of any coin: did it have to survive anything? A century of commerce, a government melt, a shipwreck? Then condition is a story and scarcity is real. Struck last year for a velvet box? Then perfection is the default, and the price should reflect metal and craft, not manufactured rarity. Our companion piece on what a 70 grade really means finishes this thought properly.