Q. David Bowers
The 1884-S is quite common in AU condition; bags of lightly circulated pieces may yet exist and are the source of marginal pieces. The 1884-S, along with the 1901, was probably the most consistently overgraded silver dollar in coin auctions.
The silver dollar market has a wonderful capacity for consuming and hiding large quantities of coins, and even significant groups of rarities are apt to disappear into limbo. So it was with the 1884-S. The dozen or so gems which Wayne Miller saw in the late 1970s and early 1880s are off the market, and the appearance of even a single coin would be a memorable occasion.
Prooflike coins: Prooflike coins are very rare, and those that do exist have little contrast. Apparently, cameo DMPL coins are unknown. Thomas L. Elder reported an 1884-S Proof in his J.B. Wilson Sale, October 5-7, 1908, Lot 225, but what happened to this is unknown, nor is it known if it would rate as a Proof today. In prooflike finish, Wayne Miller considered the 1884-S to be the very rarest of all DMPL Morgan dollar issues.
Probably fewer than 30 PL coins exist (six have been certified, all in lower grades), and as of September 1992, neither NGC nor PCGS had certified even one DMPL. Current population data suggest that 1884-S is the 15th rarest PL Morgan dollar. In DMPL the 1884-S is off the chart, as noted.
Caveat emptor: Watch out for S mintmarks added to common Philadelphia Mint coins to create a phony "1884-S." The American Numismatic Association Authentication Bureau, 818 North Cascade Avenue, Colorado Springs, CO will examine questioned coins for a fee and is highly recommended for all such cases.
Varieties
Business strikes:
1. Normal date: Breen-5579. Sliders are common (often overgraded: beware!), real Uncirculated scarce, gems rare, prooflikes very rare, DMPLs apparently unknown. Most likely all 20 pairs of dies were used. VAM-3 and 7 have repunched mintmarks; other varieties are positional.

Business Strikes:
Enabling legislation: As earlier, plus Act of February 28, 1878
Designer: George T. Morgan
Weight and composition: 412.5 grains; .900 silver, .100 copper
Melt-down (silver value) in year minted: $0.85904
Dies prepared: Obverse: 20; Reverse: 20
Business strike mintage: 3,200,000; Coinage figures (by months; incomplete): January June: not known; July: 500,000; August: 300,000; September: 250,000; October: 100,000; November: 150,000; December: 150,000.
Estimated quantity melted: Unknown, but possibly a million or more under the 1918 Pittman Act, etc.
Approximate population MS-65 or better: 12 to 20 (URS-5)
Approximate population MS-64: 80 to 150 (URS-8)
Approximate population MS-63: 400 to 800 (URS-10)
Approximate population MS-60 to 62: 1,500 to 3,000 (URS-12)
Approximate population G-4 to AU-58: 125,000 to 250,000 (URS-19)
Availability of prooflike coins: Very rare PL, possibly unknown DMPL.
Characteristics of striking: Most show areas of light striking.
Known hoards of Mint State coins: None.
Proofs:
None
Commentary
The 1884-S is available in lower grades but is a great rarity in high Mint State levels.