This seed spawns you in a taiga with a village nearby. On the opposite side of the village where you spawned, you can find a ravine with an abandoned mineshaft. In the mineshaft, there are a dungeon and a chest minecart with a diamond. This seed seems to just keep getting better the deeper you go.
Minecraft PC 1.10.X Seed: -6746613490626399375
This is a nice-sized village with lots of buildings, plenty of villagers, and several crop plots, but it doesn’t have a blacksmith to get rare items from. It’s still hard to be disappointed with the village considering the ravine on its eastern side.
This S-curving ravine has wooden planks and rails in the bottom that mark the abandoned mineshaft. It’s tricky to get down into the ravine safely, but once you do you can find several entrances to the mineshaft.
The Abandoned Mineshaft, Dungeon, and Diamond
The entrance you need to get to the dungeon and diamond is actually the one you can see from the top of the ravine. Enter the mineshaft at 352 / 35 / 184 and at the first fork turn right. Going straight in that direction will lead you to the dungeon with an open side.
This dungeon has two chests that provide you with gold ingots, a saddle, name tags, and iron horse armor.
Mineshafts are also known for having more than one chest minecart. You can explore for yourself to try to find one, but if you want one with a diamond, you’ll have to go back out to the ravine and go into the tunnel at 342 / 36 / 187. Take the first right you come to, walk all the way to the end, and then go left.
At the end of that tunnel, there will be a one block tall slit that shows you another set of mine tunnels. Mine down into that new set of tunnels and follow it down to the fork. Turning right, you should see the chest right there. (320 / 33 / 159) This chest will give you a couple iron ingots, a gold apple, and a diamond.
Keep exploring for yourself and see if you can find any more great stuff!