Obverse Dies: 4 Known With Type I Reverse and 10 Known With Type II Reverse
1878 Philadelphia dimes are considered a tougher "common" date to locate. The Type I reverse variety is very scarce in all grades including a R6 designation in Mint State. Examples of 1878 dimes with a Type I reverse should command a premium. In general, nice higher grade 1878 dimes are currently underrated when valued at common date pricing.
Plate Coin: Fortin 103, Type I Reverse, Well Struck Even Light Gold Toning Throughout
Ron Guth: The 1878 Dime would appear, at first impression, to be a common coin, but in terms of the number of certified survivors, it is actually less common than the 1880 (with its mintage of only 36,000 pieces). On the other hand, the 1878 Dime has a population comparable to that of the 1877, which has a much higher mintage of 7.31 million.
Most certified 1878 Dimes grade MS-64, followed by MS-63. The finest PCGS-certified examples (based on the November 2011 PCGS Population Report) is a single, amazing MS-68.