Differentiating a C4, C4/C3, and C3 reverses.
Sometimes when trying to attribute late date Morgan dollars, it is best to identify the reverse hub type first. This can eliminate several VAM possibilities. The 1900 to 1904 series used 2 different hub types, the C3 and C4. The C4/C3 reverse VAMs are commonly referred to as a "two-berry" reverse. The Two-Berry reverse is thought to arise from re-hubbing C3 reverse dies with the new C4 reverse hub. Thus the C4/C3 reverse VAMs do not come from a C4/C3 hub, but from a die re-hubbing process. One of the most direct ways to discern between a C3 hub and C4 & C4/C3 is to look at Eagle's left shoulder gap. On the C3, the gap is narrower, has a "pointy" bottom, and a neck wing protrudes into the gap. Conversely, the C4 & C4/C3 reverse VAMs have a wider gap, smooth gap bottom, and no neck wing protruding. Once you decide that you have either a C4 or C4/C3 reverse, then look at the number of olive berries.
Pictorial comparisons are shown below.