I have a gold colored chain (color is similar to 18karat gold) and thought that it is not gold.
So, I tried to immerse it in a 10% HNO3 solution (already used for cleaning sterling silver so it has a slightly bluish tinge of Cu2 +). Cold: no
reaction, hot: vigorous gas evolution. My conclusion: it's brass or other copper alloy. I also dipped a real 18 (even chain) and 14 k (ring) gold
piece into the hot solution: nothing happens.
But the solution is a bit greenish i.e. that the alloy does have anything other than Cu. And the surface of the metal remains yellow on the part which
is immersed in the solution.If it is brass or bronze, then it ihas a pink color: Zn or Sn is easier dissolved than Cu.
And something other strange issue: The contents of the chain is 2.2cm3 and it weighs 22 grams (10 g/cm3), so it must contain an unknown heavy metal
heavier than Cu. It contains Ag because after dipping in the HNO3 solution I dipped it into the water the water gets a milky appearance (AgCl). But
there is not so much Ag in it as the metal is too yellow.
Does anyone know what can it be?
[Edited on 2012-8-25 by metalresearcher] |