What counts as a low mintage? Context decides it. Against a run of 5,000 a mintage of 500 is genuinely scarce, and under 100 is exceptional. But mintage alone is only half the picture: it says how many were made, not how many survive in top condition.

Tiers here run from open editions struck to demand, through the common 1,001 to 5,000 band, down to issues of 100 or fewer. Only a small number of pieces in the catalogue sit in that lowest tier.

Pair mintage with population, the count of how many have been graded at each level, and you have what our guide calls the two number rule. The Rarity Register applies it across the whole catalogue.