El Salvador, 5 centavos 1944, two KM's

Hi, this coin is listed in Numista as exists for 2 different KM's:

KM 134: Copper-nickel (75% Copper, 25% Nickel) • 5 g • ⌀ 23 mm
https://en.numista.com/catalogue/pieces1301.html

KM 134a: Nickel brass • 5 g • ⌀ 23 mm
https://en.numista.com/catalogue/pieces9704.html

Can someone explain me how to see the difference between this 2 coins?

Many thanks in advance, Oscar

By year. The KM# 134 shouldn't have a 1944 year line, according to Krause and this from the US Dept. of the Treasury showing the San Francisco mint only produced the 1944 coin with the nickel silver (Nickel brass) composition:

Wowww, ok, many thanks for this quickly answer and for the information. Shouls we make some comments in the year line 1944 KM 134 that indicates something similar to "this year line is not confirmed for KM 134 and is only confirmed for km 134a" (maybe is too long?)

I think it's best ask for the year line to be removed and members moved to the KM# 134a. I don't think there is any doubt that Numista is wrong.

Ok, I'll make this suggestion of deleting year line 1944 for KM 134 and members moved to the KM# 134a in Coin Catalog Section of the Forum.

EDIT: Done...

https://en.numista.com/forum/topic114639.html

Other similar example ... in numista.com don't exist 10 centavos de cólon 1952 to try classify KM#130a because it's different metal (copper-nickel-zinc) i think that KM#130 refer the metal (nickel-brass). Greetings Nuno Silva

Απόσπασμα: "1bluemarlin"in numista.com don't exist 10 centavos de cólon 1952 to try classify KM#130a because it's different metal (copper-nickel-zinc)

​The 10 centavos 1952 is indeed in our catalogue (https://en.numista.com/catalogue/pieces14260.html). I think you are just confused by the description of the composition. Don't forget, brass is an alloy of copper and zinc so nickel-brass and copper-nickel-zinc are the same composition, just another description.

Απόσπασμα: "1bluemarlin"i think that KM#130 refer the metal (nickel-brass).

KM# 130 is copper-nickel, not nickel-brass.

confused or not... I know there are two types of metals one is white(nickel) the other is yellow(brass) both from the same date! Where I mentioned copper-nickel-zinc comes from the book "catalog of wordl coins by cherters krause and clifford mishler 2005" pag.684

Απόσπασμα: "1bluemarlin"​confused or not... I know there are two types of metals one is white(nickel) the other is yellow(brass) both from the same date! Where I mentioned copper-nickel-zinc comes from the book "catalog of wordl coins by cherters krause and clifford mishler 2005" pag.684

​I'm sorry, but there are and never were two different type of metals for the 10 centavos 1952 in Krause, only one: KM# 130a copper-nickel-zinc (copper-brass).

These coins in that time frame were minted at the US San Francisco mint. Here's the Official US Dept. of the Treasury report showing the 1951 coins were copper-nickel and the 1952 coins were nickel silver 12% (aka nickel brass, aka copper-nickel-zinc). Note that some 1952 coins were actually minted in 1953.