The coinage of Apollonia and Dyrrhachium:

Error coins and other imperfections

15 April 2021

Contents of this page

  1. Introduction
  2. Types of errors
  3. Examples

1. Introduction

All ancient coins are imperfect in some way especially if compared to modern ones. Despite the primitive minting techniques used in ancient and medieval times, expectations towards the product varied widely both in artistic and technical terms - just compare the masterpieces of the Hellenistic age with late Roman coins, Byzantine coppers, early medieval pieces, Spanish colonial cobs, etc. Despite this, there have been certain standards in every mint regulating metal composition, flan weight, form, size, images, legends, etc. If the internal quality control  does not work well, substandard pieces may leave the mint. These are the error coins (mint errors).

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2. Types of errors

  1. Flan problems
    • Wrong metal, size, shape or texture
    • The flan cracks during striking
  2. Flat strike: the upper die was not held vertically. The coin is wedge-shaped: one side is thicker than the other and the images become shallower towards this part.
  3. Off-flan: The flan was not centered over the lower die (parts of the obverse are off-flan) or the upper die did not struck the flan in the centre (parts of the reverse are off-flan); can occur together.
  4. Double strike: During multiple blows, the die doesn't hit the coin on exactly the same place resulting in double-contour images. Can be partial or total; affecting only one side or both sides.Sometimes the flan flips over and the next blow creates a coin with imprints of both dies on both sides.
  5. Overstrike: This is not really an error.  An existing coin served as the flan for a new coin. This procedure saved the flan preparation. The original devices main remain identifiable.
  6. Brockage (incuse): One side of the coin (usually the obverse) is of normal appearance; the other side is a mirror image of the same device impressed in the flan (intaglio). If the coin sticks to the upper die unnoticed, this becomes the upper die for the new flan placed on the lower die. The result of the next blow is the brockage: the ready coin is pressed into the new flan creating the negative (intaglio = incuse) image in the upper surface of the new flan, while the lower die creates the same image in relief as usual. 

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3. Examples

  1. Coin double struck on both sides

    Xenon-Pyrba double strike

    This coin is double struck on both sides: a freshly struck coin was put again on the lower die flipped, and was struck again. Traces of the images from the previous strike are visible on the opposite side, respectively.

  2. Brockage

    Antimahos brockage

    On the left we see the obverse of a cow-calf/type drachma, cow to right, eagle on fulmen above, name: Antimahos. The other side shows the exact mirror image of the obverse in incuse.

    Brockages occur in any coinages; but here two conclusions can be drawn regarding the Greek-Illyrian coinage:

    • Several other examples prove that the cow-calf device formed the lower die of the drachms; brockages cannot be expected showing the image of the upper die, which would be the reverse of the drachma.
    • Only the obverse is visible, but the emission is identifiable! Eagle on fulmen above the name on the obverse occurs only with Damageos name on the reverse, an eponymous magistrate in Dyrrhachium. This drachma is an obverse brockage of an Antimahos-Damageos drachma; Class D4; Ceka 72, SNG Cop 461.

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