Found a swamp biome last night, waited until night, and fursiously fought off zombies, skeletons, and creepers so I could get a shot at slimes. Killed a few slimes. Made it home and built a few Railcraft 3x3x3 (hollow) wood+slime+iron tanks. 'Infinite water' problem has been abated for now. This *should* be enough for quite a lot of steam, a Forestry multifarm, etc.,.
Now, if I can only find enough copper and tin...
At the current rate, I may find enough small copper and tin ores from just wandering around to at least enter the bronze age. Can't wait to start smelting so I'm not wasting so much copper. I've found tons of other ores, though, and most of them are Tier 2, ex. Nickel. Also, lots of iron. Found a huge iron vein at around Y=15.
Amazingly, Cobalt is pick-able with a stone or flint pickaxe and is a level 3 ore and is vanilla smeltable ! I've made some amazing tools with cobalt ingots and plates.
I'm not sure if this is a GT 5 for 1.7.2 thingy or a GT 5.x for 1.7.10 thingy.
Oh, and I found a very nice diamond vein
Interesting how GT 5 diamond is an ore, and when picked, drop an ore block. You then smelt/macerate/etc.,. to extract the diamond. In this era, the yield is 1 for vanilla smelting. In later eras, it looks like the yield is over 2x per ore.