The logo introduced in late 2013, and updated in 2014 represents an axehead.
Earlier SharperIron site designs featured a bullseye and, later, a sword. Since ‘08, however, the site has prominently featured an axe, axehead, or some portion thereof.
Why an axehead?
An axe may serve not only as a weapon for tearing down but also as a tool for shaping and building.
When the poet penned the words of Proverbs 27:17 (“As iron sharpens iron, so one person sharpens another”), it’s unlikely that he and his readers thought only of weapons and battle. Far more often, sharp iron was the means of getting work done—building things, repairing things, working fields, providing for your livelihood and your family.
The axe aptly represents both the Proverb and the New Testament prinicple:
Therefore let us pursue the things which make for peace and the things by which one may edify another. (Rom. 14:19)