Font Awesome
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fa-mars · Unicode: f222 · Created: v4.3 · Categories: Gender Icons

After you get up and running, you can place Font Awesome icons just about anywhere with the <i> tag:

Example of mars fa-mars 
<i class="fa fa-mars" aria-hidden="true"></i>

Note: to improve web accessibility, we recommend using aria-hidden="true" to hide icons used purely for decoration.

Looking for more? Check out the examples.