The concept of creating a collection.
Over the past centuries, a mass of coins has been minted, the number of which can be estimated in the tens, perhaps about 100 billion examples. At the same time, the number of types of coins is probably in the hundreds of thousands.
Obviously, such an “ocean” is not so easy to navigate, and there are many “navigation charts” (catalogues) for collectors, following which you can explore in great detail any relatively small part of it, in any case leaving a large part “overboard”.
I think that for those who wish to explore this "ocean" as widely as possible, there is nothing else but free navigation, wherever your heart desires, that is, to those coins that you like. But in order for the couple of coins thus acquired to become a collection, there must be some principle according to which the coins take their place.
Coins are direct participants in many important events in history. Whether it be military companies or grandiose construction projects, they are present in them as payment to soldiers, architects, builders. Truly great deeds require significant financial resources, and it is often possible to correlate any type of coin with specific events, which we read about with interest both in the writings of ancient authors and modern historians.
Such historically significant coins have a universal character: the sphere of their circulation covers large territories, they are issued in huge numbers and for a long time, which for the most outstanding types is centuries. Their popularity is so great that almost all coins of this kind have imitative issues.
Thus, choosing for the collection a universal coins of different times and peoples, you can literally hear the breath of History, touch the masterpieces of different eras and feel the pulse of the economy.