Below is what the SCWC has to say. The Nickel coin will be magnetic the copper- nickel coin may or may not be and as they were made in 2 places the planchets could be different some may be and some may not be (magnetic). It appears that some of the copper - nickel coins were made in Bombay and have a mint mark
Copper nickel coins are usually softer and wear more but it depends on the mix
Hope this helps
KM# 105 4 FILS
4.0000 g., Nickel, 21 mm. Obv: Head left Rev: Value within center circle flanked by dates Shape: Scalloped
Date Mintage F VF XF Unc BU
1938 1,000,000 1.00 2.00 6.00 20.00
1938 Proof
1939 1,000,000 1.25 2.50 10.00 35.00
1939 Proof
KM# 105a 4 FILS
4.0000 g., Copper-Nickel, 21 mm. Obv: Head left Rev: Value
within center circle flanked by dates Shape: Scalloped Note:
Struck at Royal and Bombay Mint.
Date Mintage F VF XF Unc BU
1938 2,750,000 0.75 1.00 2.00 15.00
1938 Proof
1938 -I 2,500,000 1.00 2.00 7.50 15.00 —
KM# 105b 4 FILS
4.0000 g., Bronze, 21 mm. Obv: Head left Rev: Value in center
circle flanked by dates Shape: Scalloped
Date Mintage F VF XF Unc BU
1938 8,000,000 0.50 1.00 2.00 15.00
1938 Proof
Another way to tell them apart (especially if you do not have a magnet handy) is that the copper-nickel version (N-12678) has a small dot under the bust of King Ghazi I on the obverse, while the nickel version (N-8600) does not have a dot in that location.
also has a small dot under the bust of King Ghazi I on the obverse, but that version of this coin should have a brownish color rather than the dull silver/gray color of a copper-nickel coin, so it should be possible to tell the two versions apart by color alone (unless the coin is very dirty).
The Numista page for the copper-nickel version (N-12678) has the dot listed under the “Mint" section, implying it might be a mintmark for the Royal Mint/London/UK, but the dot is also present on the bronze version of this coin (and the “Mint” section for that page does not mention the dot).
This coin is also interesting in that it was made from three different alloys for the same date year. Typically, you might see one alloy change for a given date year for a coin, but two alloy changes in the same date year isn't very common.
It does include the km105a, but not the Indian minted coin with the mintmark “I”, km105a, and that doesn't look like being cu-ni?? I might be wrong, the Indians might have added too much Cu to the mix (https://en.ucoin.net/coin/iraq-4-fils-1938/?tid=91064)?
You state there are three types which is true but one of the types has 2 varieties. If someone has the KM# 105a type with the I mintmark they would be lost looking at your graphic.
The picture is from the Numista page ans has to be Cu-Ni as that's the only one with I mint mark.
