This story begins back in May, 2022 with Stacks Bowers Collection probably of the greatest collection of Portuguese India Coinage to cross the auction block of this firm let alone anywhere else in the world. Here is the initial offering of the piece
https://auctions.stacksbowers.com/l...t-ngc-ef-45. The first issue with the piece was its improper attribution as the reverse shield does not match any Rupia issue between 1799-1816 but is linked to KM#112 and not to KM#'s 205,219 or 220. This makes the issue c.1726-1752. Some of the very ghosted peripheral legends even match perfectly to the KM#112 portrait as on the obverse right side as we see the bottom of "S" of ESVRP. Be that as it may ... now the error part. Since these issues were struck by a hammer & anvil process and using some basic principles on what can cause weak peripheral legends lets explore this issue more closely. The hammer striking method used for Portuguese India coinage involved manually striking a heated metal flan (blank coin) between two dies with a heavy hammer. This method had several drawbacks:
Inconsistency: Each strike could vary slightly, leading to differences in the final coin's appearance due to inconsistent striking, metal flow issues and alignment problems.
Die Wear: The dies used in hammer striking wore out relatively quickly, resulting in weaker impressions over time.
Manual Preparation: The flans were often manually prepared, which could lead to irregularities and flaws in the coin blanks.
Difficulty in Striking Edges: Striking the edges or periphery of the coin evenly was challenging, resulting in weak peripheral legends.
These factors combined to make the hammer striking method less precise and more prone to producing coins with weak or inconsistent legends and designs which we always see with this coinage in small areas here and there. However, in this case we have FULL 360* obverse/reverse peripheral BLANKED OUT legends! We also have lathe marks (i.e., circular) below the obverse portrait as an attempt to polish the working die to provide a proper linear surface prior to the die details being engraved into the working die. Lathe lines by themselves can even create improper striking of a coin issue in some cases. This is not die wear or metal flow issues but probably an ill prepared working die having a SEVERE convexity (i.e., cone shaped) in its shape thereby creating a sharp central impression but no clear outer motifs. The lathe grinding operation was OBVIOUSLY incomplete/inadequate yielding a non-linear working die surface. UNIQUE in this series and probably the most complex error in Portuguese India Coinage I have encountered! John Lorenzo, Numismatist, United States
Posted 12/02/2024 12:41 pm
