I'm trying to remember the name of a book series of which I remember only the following, with Google yielding no results.
- the name of the author starts with a Z
- the main character is a knight in an household with a name sounding like Malachai who goes on a quest with six others guys and girls (a bard, another knight, a priest, etc.) and each of them finds a stone of colour which has a power on various things (like fire, their mood or water) and then they set toward a quest to beat some ancient evil.
- I used to find the book at the local library 10 years ago in France (but it was translated).