A fantasy book with dragons, elven slavers and human mages

Question

A while ago I read a series of 3 books, which were about a human girl, whose name I don't remember, but was abbreviated to Shana.

She was raised by dragons, which fled their world because it was too dangerous. Most of the humans were kept as slaves by the elves, who feared their proficiency with magic. I also remember a group of free men, who found out that iron can block elven magic.

The series had two authors, and I remember the series would end at the 4th book but sadly one of its authors had passed away.

Answer 1

An extremely quick Google search shows the result: The Halfblood Chronicles by Andre Norton and Mercedes Lackey.

It satisfies most of your requirements:

• series of four books, with the last book never being released due to the death of one of its authors (A. Norton);

• human girl, named Shana, raised by a dragon (Alamarana);

• humans enslaved by the elves;

• some humans, known as wizards, were free halfblood (half-human, half-elves), and were highly proficient in magic;

• there is an additional group, known as the Iron People, who had successfully escaped the elves after learning that iron can block elven magic.

The only problem is that, in this book, Shana is expelled from the dragons' world, so it's not true that dragons fled their world. However, I've never read the book, and I don't know how much we can trust Wikipedia on this topic.