...he removed it because minable emeralds would have ruined the point of trading.
I don't want to start arguments, but even with it's rarity do you think it'd ruin trading? My problem with that quote of yours is that we aren't trading person to person, we're trading person to computer and that we are either using the emeralds we have to get items that we could've gone off and made/obtained by the time we actually mined any. Another thing with them being so rare is that you could trade other renewable items to profit.
. . . you can't have something be minable and the basis of a economy at the same time.
That doesn't make sense. Gold and silver are mineable (in reality) and have served as currencies in numerous cultures. Furthermore, we can already trade renewable resources for emeralds, so allowing emeralds to be mined makes them no more renewable than they already are.
The thing is, you're not getting how currencies work. I'm all for new biome specific ores, but you can't have something be minable and the basis of a economy at the same time. To quote something I wrote on another thread that applies here: They're just barely rare enough right now for them to function as a currency, but they're not valuable enough per emerald to warrant having that kind of rarity. He didn't remove it because people thought it was "too rare", he removed it because minable emeralds would have ruined the point of trading.
Tangible currencies worked for thousands of years Gold, Silver and Salt for example, were all used and highly valued as currencies. Its only been in the last few hundred years that people have switched from tangible currencies to promissory notes with little to no intrinsic value.
I personally don't see how running across a fairly rare biome specific gem would have ruined trading since it would be far more efficient to build a wheat farm to the same end. Running across an emerald here or there would have made for a nice little reward.
I find his removing it to be fairly unreasonable. The only reason to remove something is if people complain that it shouldn't be in game, even then removal should be considered carefully, and only if there is an overwhelming (multi-million user) complaint. No one said that emerald ore shouldn't be in the game, just that it shouldn't be so rare. I currently have no opinion other than that it should be in game. So if you read this Jeb, then please add the ore back into the game.