(I am not a native english speaker, so I'm not really aware of the specific terminology.) A few years back, I found an unidentified rock on a beach in Normandie (France). It looks and feels (texture-wise) kind of like a metal, but it displays big cristals. It has orange tones very reminiscent of iron oxide, and the head of the cristals is dark grey. Here are a few pictures : The measured volumic mass of the piece is 3.4 g/cm^3. Could you help me figure out what this mineral is ? Thank you in advance
Your mineral specimen is most likely goethite after pyrite, a common pseudomorph found in many different geological environments.
A quick google search revealed pyrite and goethite can be found in Normandy.
Mindat - Goethite (map before from Mindat)