The charcoal tattoos on Oetzi's body were created by piercing the skin with a sharp bone or copper tool, using the 'hand poke' technique. This is demonstrated by a study published in the European Journal of Archeology by a team of American researchers.
A professional tattoo artist reconstructed the ancient technique by drawing on his own skin the same signs impressed 5,300 years ago by the Similaun man. The results demonstrate that Iceman's drawings do not have characteristics compatible with tattoos made by engraving, but are more similar to those made with a pointed instrument.