I was recently discussing EPUB Tools and the Symbol Font -> Unicode functionality.
It made me think of Webdings + Wingdings + Wingdings 2/3. When I tested with those four fonts, EPUB Tools exported the characters as your basic "abc" instead of converting to the Unicode equivalent glyphs:
- Normal Text
- Webdings
- Heavy Check Mark: ✔
- Bicycle: 🚲
- White Large Square: ⬜
- Wingdings
- Cancer: ♋
- Leo: ♌
- Virgo: ♍
- Wingdings 2
- Heavy North East Pointing Bud: 🙦
- Heavy North West Pointing Bud: 🙤
- Heavy South West Pointing Bud: 🙥
- Wingdings 3
- Right-Shaded White Rightwards Arrow: ➩
- Leftwards Back-Tilted Shadowed White Arrow: 🢨
- Back-Tilted Shadowed White Rightwards Arrow: ➫
Here is the Unicode 7.0 documents when they introduced all of the glyphs:
http://std.dkuug.dk/jtc1/sc2/wg2/docs/n4022.pdf
http://std.dkuug.dk/jtc1/sc2/wg2/docs/n4115.pdf
http://std.dkuug.dk/jtc1/sc2/wg2/docs/n4239.pdf
These have tables listing the Wingdings/Webdings IDs -> Unicode #.
I also found this site which lists the HTML equivalent for Wingdings + Wingdings 2:
http://www.alanwood.net/demos/wingdings.html
http://www.alanwood.net/demos/wingdings-2.html
although that HTML site seems to be be dated. He says many of the Wingdings don't have an equivalent UTF-8... even though they are all spelled out in the documentation (as far as I can see).
Side Note: I was also able to use BabelMap to generate a giant list of characters added in Unicode 7.0 (see attachment) + the Symbola font here:
http://users.teilar.gr/~g1951d/
Maybe that might help in some way.
Side Note #2: Maybe you could subset/embed those symbols if needed. Many of those more obscure symbols don't even appear in most fonts (many don't even appear for me in Firefox. I shudder to think of their support in most ereaders). But converting them to actual UTF-8 will be infinitely more useful than the current "abc"s.