Is a 70 always worth more than a 69? Usually, but not always by much. The gap matters most when few examples reach the top grade. Where thousands have been graded 70, the premium narrows sharply. Grade is one of two numbers that describe scarcity; population is the other.

The letters before the number describe how a piece was made rather than how well it survived. MS means mint state, a standard production strike. PF or PR means proof, struck with polished dies for mirrored fields.

Our Grading 101 guide walks the full scale, and the population guide explains why grade alone never tells you how rare something is.