Skull with Halo tattoo

Ah, a bit of a vague question here! =P

I believe you are talking about the Halo Legendary Icon tattoo.

Pictures courtesy of HBO:

Traced:

http://nikon.bungie.org/images/legendaryskulltattoo.jpg

Partially Shaded:

http://nikon.bungie.org/images/0809070001uk6.jpg

If this is not what you meant, please alter your question.

I hope this has helped you; if you have more questions, my Gamertag is below:

Gamertag: PyT Shad0w, Level 50