Holey dollars and dumps

Just a couple of examples of a holey dollar and one of a dump. The references are to the Mira/Noble catalogue20 "The Holey Dollars of New South Wales".

For identifying the original coins, the best reference I have is Yriarte and Sanchez21 but that may be a difficult resource because only 2000 copies were ever printed.

Holey dollar 1798/8
| Obverse 1798, Charles IIII
| Reverse Mexico mint (see mint mark 'o' over 'M' at the 8 o'clock position)

A 1794 example of the original coin may be seen by clicking here or on the picture.

1805/24
| Obverse 1805, Charles IIII
| Reverse Potosi mint (see JPS monogram at the 8 o'clock position.)

A type A/1 dump

In these pictures, the dump is not on the same scale as the holey dollars. The holey dollar is shown at one quarter resolution whereas the dump is shown at one third resolution. This means the dump looks larger than it should in comparison to the ring dollar.

Even if the pictures were to the same scale, the dump would be larger than the hole in the ring, although the difference would not be very noticeable. The diameter of the hole is 17mm and the diameter of the dump is 19mm. This meant that the dump spread quite a lot under the pressure of the counterstamp dies. The absence on dumps of features from the original coins has been interpreted by some writers as suggesting that the dumps were smoothed before being struck. On thinking about it, I doubt that it was done. For a start, filing the dumps would have been a really tedious and wasteful process. Secondly, given the substantial metal flow in spreading a 17mm blank to a 19mm finished coin and the strike pressure needed to make that happen, one would expect that any features on the original coin would be obliterated without any need for smoothing.

Incidentally, the dump has a milled edge suggesting it was struck in a milled collar. Dr Mira tells me this wasn't done; the milling was added afterwards by a procedure known as rifling.

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