Aye - I always think of two stages:
1 safe
2 ready
Safe is when it stops zapping. That's easy to find (zap test!)
Ready is harder to define as it varies from recipe to recipe and person to person. Even then, each person will have, or at least I do, different stages of ready - good enough for me to use and good enough for giving away to family and friends. I am happy to use a 4-week old salt bar if I want to see how the new scent works or what not, but I wouldn't really give one away at that stage.
1 safe
2 ready
Safe is when it stops zapping. That's easy to find (zap test!)
Ready is harder to define as it varies from recipe to recipe and person to person. Even then, each person will have, or at least I do, different stages of ready - good enough for me to use and good enough for giving away to family and friends. I am happy to use a 4-week old salt bar if I want to see how the new scent works or what not, but I wouldn't really give one away at that stage.