[JuiceWeasel]

Hello, I am currently running an experiment on how to Identify Zinc Alloy and regular Aluminum. This was an Idea which was Airsoft related....The story is that some Airsoft guns are made from different metals, and materials. I wanted an easy way for airsoft players to identify the composition of metals in their airsoft guns. To date the different metals I know of are Zinc Aluminum, Magnesium Alloy, Steel, Brass, Aluminium and probably some airsofters may add Nickel, Silver and Gold plating. My first suggestion was to do a hardness test/ scratch test; but due to the 2 metals having similar tolerances to wear, and some being made differently, I chose not to use this tactic. There were other suggestions I found online, such as finding the mass. However I do not have a beaker or a scale to test this. Instead I used Bleach/ Weak Chlorine
to use as a test. I inserted my broken airsoft barrel, a piece of pencil lead (Zinc?) and Aluminum foil into a glass filled with Chlorine (Outside) and waited. Here are the results... The aluminum had two little holes and discoloration. The barrel however was interesting you can decide if these are Chlorine Crystals or Zinc Chloride or whatever...I used (Great Value Bleach) (The piece of pencil lead did nothing.... so it is pot metal?)





I must say there is alot of build up where the metal is exposed... Is this test reasonable? Any recommendations?

Sorry for any bad grammar and spelling.

Thanks In advance

[Hunter2]

I think in this way you will not find out what material its. Both Aluminum and Zinc react with chlorine to their chlorides. Pencil normally made by graphite and not lead anymore. That is the reason you don't see a visible reaction with it.

I would dissolve a sample in acetic acid or hydrochloric if available. This solution you can treat with Potassiumhexacyanoferrat. Zinc will give a white precipitation. Aluminum does not. There more color reaction can be used. Like Alizarin.

[JuiceWeasel]

I do not have concentrated Acetic acid or Hydrochloric acid...I could probably find an alternative. I do not know where to find Potassiumhexacyanoferrat or Alizarin...hmmm there must be another way. The only way I can differentiate between Zinc Alloy and Aluminum is brittleness and how the metal reacts to oxidation.

[billnotgatez]

If you  want some information.

http://en.wikipedia.org/wiki/Alizarin
1,2-dihydroxy-9,10-anthracenedione

http://en.wikipedia.org/wiki/Potassium_ferricyanide
Potassium hexacyanoferrate(III)