It's straight out of the MS Webdings font, from 1997:

http://en.wikipedia.org/wiki/Webdings#mediaviewer/File:Webdi... (top row, 3rd character)

Is there an emoji for "Piracy"?

edit: Found elsewhere

>[...] another new character (#1F571) depicts the familiar skull and crossbones. It is labeled “skull and crossbones” too – no “Yes to Piracy” here.