Since you wanted to make money for your new house I voted for China due to the fact that you'll be guaranteed to find plenty of platinum and mercury laying around the map. There's a chance you can make a great deal of money if you can find Tiberium ore. There are two large rocks in front of Han's Orchard where occasionally Tiberium will spawn but mostly you'll get faked out with Jade and Emerald (bleh) but it's worth trying. Make sure to check relic vendor every day for Platinum or Mercury or hopefully Tiberium. If you choose to instead go to Egypt I would suggest you go to the pyramid of the sky at the top of the map. If you are standing at the entrance, turn around and look out into the distance. You'll see an oasis and further out a sort of small valley with sand and some trees, walk past the oasis (which will be on your right) and continue towards the end of the valley. You should see the bottom of a hill of the left before the end of the valley where high level ore can spawn including Tiberium. Further out at the end of the valley you can find mummitomium, another valuable ore. Check the relic vendor everyday for both Tiberium or mummitomium. Alternatively you could complete the pyramid of the sky and pick up the treasures along the way. At the end there is a life fruit plant and a death flower. You can return at any time to harvest the life fruit.
If you are fortunate enough to find valuable ore, making the most out of it will depend on what ore we are talking about. Make sure you finish the ore collector challenge that gives you the chance to receive multiple ingots in the mail when you smelt ore. Send any platinum, mercury or mummitomium away to be smelted or really any ore that you find that's $54 or more in value. Tiberium is different though. Ideally you'll want Supernatural installed so that you have access to the gem cutting machine. You can purchase one or you can use the one at the elixir consignment shop. Cut the tiberium with the gem cutting machine into a small spire. You will also receive 1-6 tiberium gem dust. Move the spire and the gem dust outside of your sims inventory onto your home lot but don't place them right next to eachother or other objects, they will grow into a large spire but they will need space to do so. They should grow after a day or so left out of the inventory. Each large spire of tiberium should be worth anywhere from 30-40k or more. Take these large spires to the elixir consignment shop and consign them. The large spire should sell for around twice their original value. I don't quite remember all the factors that play into how much stuff sells for at the consignment store. In any case it's going to be a large chunk of change for your newly weds to start a family. If you do not have Supernatural installed you can move the raw ore out of your inventory and it will grow into a large spire.
I hope this wasn't overwhelming or didn't make sense. Didn't mean for this to turn into a speech. For more information on metal collecting you can find it
here. For more information on Tiberium, you can find that
here.
Some additional notes if you decide this is the route you want to go to raise money for your newly weds. You can buy any ore you have access to through your expansions at an ambitions consignment store. Also If you don't have concerns about how this may change the balance of the game, you can place a relic register on a commercial lot. I believe they are in build mode / community objects / Misc. Though I could be wrong, I'm foggy at the moment, been sick for days. They won't sell relics but they will sell raw ore and gems. Though sometimes their inventory may be empty. I always build a shop at the junk yard that sells ore. Additionally there are some bugs you might be aware of. The first small spire I cut won't grow into anything. This can be avoided if I have more than one piece of ore to cut thus giving me more than one small spire. Since this is a bug I can't find info on, I suspect is effects very few people. Just don't be discouraged if you encounter it because it shouldn't last past the first cut. Also, if you have high free will on you can choose to not give your sim a command after you've cut all your tiberium. They may choose to autonomously use the machine again and for some reason (bug reason) they will cut another piece that you don't have and it may continue on like that giving you small spires and gem dust for as long as you choose to let them do it. This feels cheaty though in my opinion because it's clearly a bug and Tiberium already makes you so rich to begin with but that's up to you.
