Is it possible to convert a font icon back into it's private use code?

Is it possible to convert a font icon back into it's private use code?

For example, I am using fontAwesome, and I have a span that contains an icon:
written in html:
<span class="icon">&#xf05a;</span>
though once actually rendered on the page:
<span class="icon">ƒÊ</span>
Is there any way to retrieve the special character code f05a once it has
been rendered?
i.e.
var
code = $('.icon').html(),
privateUseCode;
console.log(code); // ƒÊ
?????
privateUseCode = '\f05a'; // or similar
Much appreciated!