On October 12, 1911, a series of stamps commemorating the Centenary of Independence was issued. All values were printed by the South American Bank Note Company of Buenos Aires.

The sheet size of each value was 50 - 5 horizontal rows of 10. The perforation on all values is 11½. All values are bi-colored. I have no records of any quantities issued.

According to a lot in the 3 December 1991 Christies auction, there are some bromide essays with different centers, hand painted inscriptions or manuscript observations or endorsements signed by Juan P. Perez.

Kneitschel notes 11 combinations of colors on bright card and 10 combinations of colors on paper for plate proofs. I have seen the following on card:
FRAME CENTER
orange yellow blue
green black
green brown
carmine blue

I do not have a record of any proofs for this value. The only varieties I have recorded are: Imperf pair; head of liberty doubled.

Again, I have no record of any proofs for this value and the only variety is an Imperf pair.

I record a sheet of 50 for the value and they may exist for other values. I do not record any proofs for this value and the only variety is an Imperf pair.

The only variety is an Imperf pair. I have no record of any proofs for this value.

Kneitschel lists 38 combinations of color on bright card, 28 combinations of color on paper, a blue and black with center doubled, an olive and black with center doubled, and an orange and blue, perf 11½, gummed with center inverted as proofs for this issue. I have seen the following:
On blued card
FRAME CENTER
rose blue
red violet dark blue
red violet green
green black
orange brown blue
deep red violet dark blue
On white card
red violet brown
pale red violet green
green black
dark green green
green blue
dark green dark blue
dark blue dark green
dark blue green
dark blue orange brown
pale green orange brown
brown dark green
brown green
dark green red violet
carmine black
red violet orange brown
red violet dark green
olive brown black
olive brown red brown
olive brown red violet
dark brown black
On paper
dark green dark blue
red brown dark blue
olive brown dark blue
carmine black
orange yellow black
dark blue black
red violet dark green
brown dark green
dark green red brown

I also record the following essays: Die Essay of Center Only in green; Die Essay of Frame Only in dark blue. The only variety I record is an Imperf pair.
An unusual cover shows the 50c + the 1913 5c and 20c going to China via Europe and Suez. It is a registered cover and has the Shanghai markings on the front.

I do not record any proofs or varieties for this value.

On 28 August 1912 a provisional issue - 20 centavos on 50 centavos - was sold to the public. I do not have any record of the quantity issued nor if there are essays or proofs for this stamp.

I record the following varieties:
bar omitted (position #91 on sheet of later printings.)
pair, one with normal, one with double overprint
pair, with and without overprint
overprint double, one vertical
overprint double, both inverted
overprint inverted
overprint double
pair, one normal overprint, other double with one vertical

The most interesting cover I have recorded is a strip of 3 with inverted overprint on a Registered, AR cover. Covers with this issue seem to be scarce.

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