Question: How do you find all the metals to test?

Jade Owen answered on 15 Jun 2015:

First of all you need to digest what you want to test in acid!
For most metals (e.g. iron, aluminium, nickel etc) acids like nitric acid or hydrochloric acid will work.
For other tougher metals (e.g. gold, titanium) mixtures of a few different acids is needed to be strong enough to digest it!

Once you have done this you can they use some equipment to test the sample solution you made. My favourite is called an ICP-OES (inductively coupled plasma – optical emission spectrometer).
It uses a plasma to break up the sample into atoms and to give the metals in the sample energy. (Plasma is similar to a flame but much much hotter! Can be as hot as the surface of the sun at 7000⁰C) The energy then turns into a specific light that comes from the metal – just like a fingerprint! So aluminium shines one type of light while iron will shine a different colour. How bright that light is will then let you see how much of that metal is in your sample.

I once saw a sample that had so much sodium in it the chamber shone orange just like a traffic light!