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 Replies: 10 / Views: 759 |
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Pillar of the Community
United States
2637 Posts |
40 mm, 25.35 grams. Could this be a contemporary counterfeit?   |
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Pillar of the Community
United States
1757 Posts |
Absolutely and it appears its GNL-UNLISTED with no plate match to Gurney's book. Congratulations.
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Pillar of the Community
United States
1962 Posts |
Figuring 1816-1818 Zacatecas pieces is a complicated task. SOOOO much variety and crudeness...
This piece doesn't smack me in the face as an immediate "oh, that's non-regal", and neither does the slightly low weight.
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Pillar of the Community
United States
1757 Posts |
Agreed. The low weight and the date and motifs seem very similar to other Z mint pieces in GNL. Realeswatcher I would not officially give it a GNL number without a hands on inspection or minimally a minimum 90% Ag Sigma Analyzer test. Yes XRF would be better. I would buy it as a CCC without hesitation. Its a win-win coin. No worries.
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Pillar of the Community
 United States
2637 Posts |
Thank you both for your input on this coin. The LCS stated that it did not even register 80 percent on the sigma.
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Pillar of the Community
United States
1962 Posts |
Quote:
The LCS stated that it did not even register 80 percent on the sigma What DID it register? |
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Valued Member
United States
131 Posts |
I've always been a little skeptical of sigma results since they are basically metal detectors. Their results are more believable on modern bullion coins or Morgan dollars, etc. that are very standardized. A home specific gravity test by water displacement would show whether it was significantly debased or not. |
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Pillar of the Community
United States
1962 Posts |
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A home specific gravity test by water displacement would show whether it was significantly debased or not. Though a decent gold presence in the alloy could screw that up slightly... I would love to see a really perfectly constructed study where a batch of coins, including good "test" examples (silver eagles, 1921 Morgan, etc)... were tested every which way and we could compare the results across the board. Specific gravity (done with legitimate scientific accuracy), handheld XRF, desktop units, other elemental analysis devices... maybe run comparisons where you calibrate to look for EVERY trace element vs. just, say, 6 or 7 basics (silver, copper, etc.). Compare ALL readouts and see what we find. Obviously John has done a lot of testing... Bob does specific gravity perfectly and has had much testing done... but I mean where we really have a sizable data set to look at across specimens. Completely cost/time/access-prohibitive... but would be nice as a reference. |
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Pillar of the Community
United States
1962 Posts |
I mean, geez, LOOK at the variety observed within 1818 Zacatecas... the bust, rest of the punches/detail... weights... patina...
acsearch.info/search.html?term=1818+(zacatecas+Zs+ZsAG+ZAG)+%228+reales%22&category=1-2&lot=&datetmp=no&date_to=&thesaurus=1&images=1&en=1&de=1&fr=1&it=1&es=1&ot=1¤cy=usd&order=3
BTW, note that for many/most of the pieces where weight is provided, it's in the 25._g to low 26._g range.
And then you really should look at the minors as well... which are just as kooky/varied.
Trying to make any sense of this coinage requires viewing and studying 10x over EVERY example you see... and also having a grasp of numismatic/historical research of the goings-on at Zacatecas mint and in general during the WOI period.
Edited by realeswatcher
12/05/2023 10:08 am
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Pillar of the Community
United States
2637 Posts |
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What DID it register? The lowest purity silver setting on the LCS' sigma device is 80%. So the owner was left with the conclusion that the silver content, if any, was less than that percentage. |
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Pillar of the Community
United States
1757 Posts |
Realeswatcher is right if this was my coin I would do an XRF analysis. Worst case is pay $75 for some company that does this analysis for that amount on ebay. If you contact me after verifying its large debasement with copper say >20% or more via an XRF assay I can supply a GNL# to the piece. But at this point being non-XRF we can only say GNL-non listed. John Lorenzo |
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Replies: 10 / Views: 759 |
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Posted 12/04/2023 03:12 am
