Ron Guth:
In 1870, the mintage of the Nickel dropped substantially, but still rang in at nearly 5 million pieces. Though the total population for this date dropped as well, the grade distribution of Mint State examples mimics that of previous years. In other words, MS64 is the most frequently-seen grade, followed by MS63, then MS65. At the top end is MS66, where PCGS has certified a total of ten examples, but none finer.
Most examples of this date are struck well, but die cracks are common. Often, the reverse stars show outlines; this was not caused by repunching, but by impressing the hub too heavily into the die.