Peru Un Sol (1885), Overmarked by Guatemala

Obverse: FIRME Y FELIZ PORLA UNION UN SOL Reverse: REPUBLICA PERUANA LIMA .9 DECIMOS FINE R.D. 1885
Obverse counter-stamped: REPUBLICA DE GUATEMALA 1/2 REAL LAGRANGE (30 DE JUNIO DE 1871)Reverse counter-stamped: 0.835 1894 (LIBERTAD 15 DE SETIEMBRE DE 1821)

I had never expected to get this coin, but paid a handsome money to get this. I don't know much about this coin except that (said to have been) circulated around in Tanah Melayu. I had also identify this coin from Saran Singh's as foreign circulated coin.

It is interesting though, to get this one into my collection.

What makes it more interesting is the fact that is has counter-stamped, Republica de Guatemala 1/2 Real (1894).

Click on respective image to enlarge. If you happened to have some information or like to raise question, please comment into this post.
Updates (2008-06-30)
I have luckily found information on this coin from Krause. Catalog number is KM#166.22 (1885 RD) 0.9 Silver 0.7234 oz. Minted in Santiago.
It has been counterstamped 1/2 Real (Medi0) Guatemala, exergue 1894, catalog number KM#165.
Counter-stamped coinage is cannot be found in any catalog, hence I have to find their specific catalog number.
Interesting information
By 1894, foreign coins had become so prevalent that on August 10, the government authorised their counter-stamping at the mint, with the official 1/2 Real dies of 1894, to legitimize their circulation.

Mint Assayers Initials
The letter(s) following the dates of Peruvian coins are the assayer's initials appearing on the coins. They generally appear at the 11 o'clock on the colonial coinage and at the 5 o'clock position along the rim on the obverse or reverse on the republican coinage.
Note: I still cannot find the name of the assayer (R.D.) Please write something if you know.


Information about this coin has been updated officially at:
http://www.exonumi.com/?page=publish&id=1.131.CN.cb1f0