I have looked over sunset valley, had my sim go to every single marker provided by the Collection thingy they get as a lifetime reward, no luck finding the Rainbow Gem and Pink Diamond...is there some secret? Does he have to have something in his inventory or is it at a paticular time of day or is it just a matter of Rummaging through the garbage cans (my one other sim found a pink diamond by doing that)

Just luck, keep trying and you'll eventually come across them. They don't respawn every time. I've been over the map like 7 times, only ever found 3 Pink Diamonds.

Apparently collecting is a hidden skill so your sim first has to skill up before these will spawn. That's not entirely true. Someone in your town has had to have skilled up before these will spawn. Once they start spawning then they will occasionally re-spawn and can be found by anyone. You can find mods to monitor your hidden skills. There is also a gem spawner mod.

Don't really like mods to much, cos they sometimes are more trouble than they worth if they get corrupted, I will just keep my sim searching and searching and searching, at least he getting very very rich from all the gems and metals he has found, (plutonium got him out of debt)

can someone explain respawning to me? If 1 Sim collects every single gem in the neighborhood, do all of them reappear or only some? Does it take a long time? And do they pop up in different places?