Nickel test
A nickel test is a chemical spot test that turns pink if nickel is present, helping to tell meteoritic metal from most man-made iron.
Meteoritic iron always contains nickel, generally at least about 5 per cent and in some irons much more. Most man-made iron and ordinary steel contain little or none, although some alloys, such as many stainless steels, contain plenty. A nickel test looks for this difference. The usual reagent is dimethylglyoxime, often called DMG, which forms a bright pink to red compound with dissolved nickel. A tiny amount of metal is dissolved from a clean spot, usually with a weak acid, and the reagent added. Pink means nickel.
The test is useful for suspected iron meteorites and for metal flecks in stony ones. An iron such as Gibeon from Namibia, with roughly 8 per cent nickel, gives a clear positive. But it cannot prove a meteorite: nickel-plated items, stainless steel and some natural nickel-bearing minerals also react, and weathered, rusty surfaces can give weak or misleading results. Laboratories confirm with methods such as X-ray fluorescence or an electron microprobe, and by etching to look for a Widmanstätten pattern.
This test uses chemicals and acid, so it is strictly for adults, with gloves, eye protection and good ventilation. Children should never try it.
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