What is the succes rate of soul stones combinations

I have been going through rare soul stones like crazy trying for an epic. So are there any Rappelz players that know what the actual odds % are before I waste everything?

The rate is a non constant 7-12% success rate on combining stones for epics in Rappelz. This is single case odds bracket which means the actual success rate for the server as a whole could be even lower.

The problem is once a player gets so invested in the process it is hard to walk away from with nothing, so they just keep rolling the dice.

In the end they may end up paying way more for an epic. This is the brutal nature of rappelz. Also make sure you consider what combination you could be dealing with too... Int?