I cant find one. Is there an exact location or am I to just keep checking trashcans and the catacombs?
I will answer my own question with the hope that it may help someone else down the line. I have lived everywhere, seen every place, done almost everything. There are 2 ways to get a pink diamond in the x box version of the sims 3. I can confirm that you can get one in the catacombs. It takes quite a few attempts. You need to send a collector sim to the catacombs. I did this while staying at my family's home. Pick the sim you sent, say no do not travel to location. Stay on this sim and you will get a story and/or options. There are bears, monsters and zombie bears down there. You must not run into them. If you do your sim will flee and you get no pink diamond. Avoid them and your sim will leap to a ledge that has a rock sometimes a space rock. Eventually it will be a pink diamond. Using karma power lucky can help a little until it runs out. The second way I cannot confirm. It is to take a klepto or a police track level 10 and search every trashcan in town over and over until you find one. There are not a ton of trashcans in town. 1 at every home. I didnt even see one at any parks.
Pnk Diamonds only show up in the Catacombs of the Specter Family Mausoleum, the yard of the Pargon Personal Private Charity Warhouse, or the side are next to the Palatial Beach Pool. Pink Diamonds are just like any other collectible. Depending on how rare they are, the less they show up. The Pink Diamond being the not just the rarest gem but one of the most rare collectibles only shows up at a minimum of once every four days at one of the certain areas it will apear in. Even after that there is a ratio that tells whether the gem will even show up or not. There's no telling how or where you will find a Pink Diamond on any particular day.
My sim actually acquired a Pink Diamond on his first and only run through the Catacombs. He did run into some bears somewhere along the line but once he jumped the ledge I got a message saying an Extremely Rare Pink Diamond was added to my inventory. I think Althletic skill might have something to do with making all the way through the Catacombs. My sim was fairly new when I made him explore the Catacombs and he still got the Pink Diamond. The only thing I can think of is his Athletic skill was high enough for him to go all the way through and it was his lucky day. I picked Lucky as one of his traits.
Here is a list of the collectible gems and their values from The Sims 3 strategy guide. Hopefully I can do all this so it makes sense. No copy and paste here :(
All values are for Uncut Gems and values are according to weight of gem.
Gem Rarity Lowest Possible Value Highest Possible Value
Blue Topaz Common 9 21
Smoky Quartz Common 15 25
Emerald Common 20 30
Ruby Common 25 35
Yellow Sapphire Uncommon 35 60
Tanzanite Uncommon 65 95
Diamond Rare 100 200
Luminorous Gem Rare 150 350
Pink Diamond Extremely Rare 1,200 1,650
That blank space in the list is supposed to have Rainbow Gem, Very Rare with a lowest value of 450 and a highest value of 700. I forgot to add it and I was not able to go back and edit again. My apologies for the triple post. I just wanted to help out so people know the gems.