Buenos Aires 1859 1p "In Ps" tête-bêche pair
| Buenos Aires 1859 1p "In Ps" tete-beche pair | |
|---|---|
| Country of production | State of Buenos Aires |
| Date of production | 1859 |
| Nature of rarity | Tête-bêche pair, Unique |
| No. in existence | 1 |
| Face value | 1 peso |
| Estimated value | $575,000 |
![](https://en.wikipedia.org/wiki/File:Stamp_Buenos_Aires_1859_"In_Ps"_Blue_Tete-Beche_pair.jpg){kind=link}
The Buenos Aires 1859 1p "In Ps" tête-bêche pair, also known as the “In Peso” tête-bêche Pair, is the only known specimen of an inverted error on Barquitos postage stamp issued by the sovereign state of Buenos Aires.
The original plates were constructed of 48 stereotype clichés. At one point, clichés were removed and reaffirmed to the wood base. During this process, one of the clichés was reaffixed upside-down, resulting in the tête-bêche error in position 33 (row 5, stamp 1), which is paired with the correct orientation stamp from position 41 (row 6, stamp 1). This error is different from tête-bêche printing varieties caused by a work-and-turn printing method because cliché errors are true mistakes, while tête-bêche printing varieties are the products of the method.