"1957" Thai 1-baht; only three official finishes?

[villa66]

Below, the three types of mint-finish I've encountered so far for Thailand's 1957 1-baht: 1) "as-struck" BU; 2) "as pickled" BU; and 3) "as-polished" BU. But is it polished--or plated? (Maybe this is how Y82.2 crept into the catalogs.) Anyway, according to the mint, #3 is also silver, but then the alloy in the '57 1-baht is practically silver in name only, so....

Pictures or other information on any other official versions of the '57 Thai baht are most welcome.

v.

[Gerhard Schön]

No idea what catalogues you are using but mine says all these 1957 dated 1 baht coins were made of an alloy of copper, nickel and zinc, which was silver clad before striking, resulting in an overall metal content of 64% copper, 23% nickel, 10% zinc and 3% silver.

Below, the three types of mint-finish I've encountered so far for Thailand's 1957 1-baht: 1) "as-struck" BU; 2) "as pickled" BU; and 3) "as-polished" BU. But is it polished--or plated? (Maybe this is how Y82.2 crept into the catalogs.) Anyway, according to the mint, #3 is also silver, but then the alloy in the '57 1-baht is practically silver in name only, so....

[villa66]

The business about the silver-plating is extremely interesting, and might be the answer.

The ’57 ”silver” baht came as a surprise to me, and my information about its overall composition is the same as yours. But I did not know it was plated—I thought maybe its surfaces were blanched before striking.

Krause 2012 lists the ’57 baht according to the old Yeoman catalog numbering system, with the .030 silver baht apparently being listed as Y82.1 “Copper-Nickel-Silver-Zinc.” Okay so far. But Krause also lists a plain “Copper-Nickel” version, although the catalog muddies the water still further by saying the coin has only “one medal on uniform,” which would seem to indicate a different type altogether. (And then there is yet another ’57 listed, Y82a, which is said to be “Silver” and “Rare.”) But never mind that last—it’s the idea of a copper-nickel baht that interests me.

I had been ready to dismiss the copper-nickel ’57 baht as a catalog mistake when I came across coin #3 above. The color is not silver. Looks like copper-nickel. (Looks also like it could be steel-plated, and I can find catalog support for that idea too, but that was just tonight when I found that catalog reference and I haven’t tried a magnet yet.)

Coins #2 and #3 come from two different types of Thai mint sets, and both have been “reconditioned,” but they clearly have two different types of finish. The mint calls #3 “silver,” but I wonder—especially as you say the silver is plating rather than alloy—if during what the mint calls its [“brilliantly polishing”] of the coins for the mint sets, if the silver plating wasn’t removed, leaving behind 1957-1-baht coins of copper-nickel-zinc alloy?

[villa66]

I haven’t had time to dig it out and test it (it’s buried very deep!), but that description of the metal of the 1957 Thai 1-baht in my old Schön catalog still nags at me: copper-nickel-steel. Nothing at all about silver, and steel?

Something about the ’57 Thai 1-baht has caused catalogers difficulty. Maybe it is the color. Here’s a better view of 2 of the 3 mint finishes—an “as-struck” original, and one of the two different “as-mint-refinished” coins.

v.