The 1878 7TF Reverse of 1879 Morgan dollar is distinguishable from the 1878 7TF Reverse of 1878 by counting the number of tail feathers and determining whether the eagle's breast is flat or rounded, with an eagle accompanied by seven tail feathers and a rounded breast indicative of the Reverse of 1879. While much scarcer than the 1878 7TF Reverse of 1878, the 1878 7TF Reverse of 1879 is readily available in the marketplace though is quite popular thus commands strong premiums especially in the Gem, PL, and DMPL grades.