Doing DCP you can get skill gem boxes, you open them and get a random skill gem which most of the time you have no idea what it is for… is it worth trading? useless and fodder for skill gem fragments? If you open your AJ and search for the gem, you only get info if you already got the drop from the corresponding monster, which will be the case like 1% of the time. It would be great to be able to get all info on every gem skill directly, not just the base class: class of the skill, monster which drops it if one exists…
In the AJ it should show the monster drop, otherwise it is cube exclusive.
About the skill effect and which class it is, I suppose IMC could do better… Best you better check either from class change UI or skill database specifically for the extra effect.
Edit: you’re right about the AJ i forgot it only show the exact one that drop.