I have noticed several instances where an 8 Reales coin has been listed as having 20 grams of silver in it. I have also wondered for years why so many Chinese fakes seem to target 20 grams as a final weight (range 18-22 grams being most common). I wondered why not at least try for 26 or 27 grams?
This error has been made by both collectors and counterfeiters. It struck me that it is most likely due to a simple error in the interpretation of the legend on the coin. This incorrect reading would provide a simple reason for why so many of the Chinese crude forgeries weigh about 20 grams.
So for discussion sake here is an example of an auction where the seller is making that error.
http://cgi.ebay.com/ws/eBayISAPI.dl...300446177740I initially hesitated to point this fact out because I do not want to have the forgers correct this obvious error BUT since it is well known that an 8R has an actual weight of about 27 grams, I felt there was more to be gained by correcting the error in the minds of novice collectors. I wonder how many collectors make the same error because they ASSUME they know what it means.
The legend on the coin above reads:
8R Zs 1830 OM 10Ds 20 Gs
This can be broken down into 5 distinct elements each of which has a different meaning and purpose. A collector should know the meaning of each of the 5 elements. Here are the elements separated and underlined.
8R.......
Zs......
1830......
OM......
10Ds 20 GsMost of the meanings are obvious - right?
8R...........Denomination
Zs...........Mint - Zacatecas
1830.........Date
OM...........Assayer Initials
But how many collectors can actually explain the LAST element 10Ds 20Gs?
That is the silver assay and it means
10 Dinaros 20 GranosThe last word is Granos NOT Gramos - it
DOES NOT MEAN the coin contains 20 grams of silver. It has NOTHING to do with grams.
Quote:
In the fineness system represented, pure silver is 12 dinaros and there are 24 granos in a dinero. Therefore, 10 dineros 20 granos is(10 + 20/24)/12 or 0.9027 fine silver.
The quote is from page xvii of "Resplandores" by Dunigan and Parker, 1997.
The Balance Scale Pesos expressed the same alloy as 902.7 which is an easier to understand notation.
Has anyone out there ever made this error?

Just for fun - did anyone notice any other factual errors the seller has made in this posting?