kernelgui
**Member** 
Posts: 18
What I collect: Primary - Canada, Secondary - British Commonwealth, > 40 Large albums of customized pages WW
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Post by kernelgui on Sept 6, 2021 16:02:20 GMT
Isn't this a rather unusual color for the 1857 3 cent? I have seen many varieties of color fades before but never anything looking so brown?? Interested in any opinions or thoughts. Thanks!  |
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banknoteguy
Member 
Posts: 324
What I collect: 19th Century US, High denomination US (> $1), 19th century covers US, Indian Feudatory States and most recently I acquired a BigBlue [with about 5,000 stamps] and pristine pages.
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Post by banknoteguy on Sept 6, 2021 16:14:45 GMT
It is an oxidized example. Here is another:
You can soak them in Hydrogen peroxide (H2O2) to remove the oxidation. Here is an example of one so treated. Treatment with H2O2 is not condoned by all collectors.
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khj
Member
Posts: 1,524 
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Post by khj on Sept 6, 2021 18:43:09 GMT
Technically, it is sulphurette, not oxidation, as this color changeling is caused by introduction of sulfur contamination. The term oxidation to describe this phenomenon has been incorrectly used so often in philately that it's fairly pointless to attempt to correct it. But technically... Also, the peroxide treatment doesn't actually remove the sulfur in this case. That's also a misnomer. It converts the thin layer of blackish contaminated ink near the surface into another sulfur compound that is semi-transparent. Granted, some of the thin semi-transparent layer will be "lifted off" during the process, but that is not the intent of the peroxide treatment. Sorry to be so picky.  |
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