I've noticed that in many other fantasy settings, there are card games or dice or some form of gambling. But this doesn't seem to exist in games or lore. Unless someone can prove me wrong.

Also, Septims had been the universal currency everywhere the Empire had control. Now that many provinces are no longer under Imperial control, have they reverted to altrernate currencies?

Do we have some lore on economy in Tamriel? We've seen taxes, fines, etc. Have empires/kingdoms become impoverished or entered a golden age? We know where ebony, glass, etc comes from, we know that Markarth is abound in silver, but where does stuff like gold and iron, as well as gems, come from in terms of regions?

There are frequent references to gambling in-game. Alcohol and gambling should never be used at the same time ~ Kharjo, Caravan guard. (Or something like that)

Septims haven't always been the main currency in Cyrodiil, although this situation is especially prevelant in other provinces. In some parts of Black Marsh the scales of slaughterfish are still used in trade for general goods and the like.

Correct me if I'm wrong, but in Arena and Daggerfall Septims were refered to simply as gold coins.

You can find iron along the tundra. It's also fairly common to find it in bandit hide outs. As for gold, I've been very fortunate to find it outside of a mine, but that's rare.

Also, the only way you can mine gems is to mine ore veins, there's something like 20% chance of finding a gem every three hits of a pickaxe.

We play a game of shells in Tribunal and we bet in the steam centurion battles, there is also the gambling done in the Imperial Arena.

Bandits in Skyrim also frequently mention about playing card games. There are also a few underground gambling operations among some groups, like with the pit wolf ring and that fighting ring in Lost Knife Hideout.

As to the Septims...maybe, we'll have to see when we get there. I can't honestly see Drakes/Septims holding a lot of weight in around Black Marsh (Outside the coast, of course), and Summerset may have already minted its own currency. Hammerfell is a different case. I can't imagine mercantile cities like Sentinel losing the currency all together when they trade in the Illiac Bay region, but I'd be surprised if they're not trying to move away from it.