I never discover metal by Mining

[onedreamer]

More likely the percent chance to discover is formulated based on the number of resources on the world map, or the number in your empire, or the number worked, or something incorporating all three.
[...]
Quit making stuff up.

well you could say the same thing about your theories. I am quite positive that the number of resources in the empire is not taken in consideration.

Anyways, I've discovered luxury resources more than once. Gold and Gems. If I don't remember bad I also discovered some strategic resources a coupla times, like coal and aluminium.

 

[MrCynical]

As I understand it there is a flat rate of about 0.01% each turn for each mine, with no other factors involved. I've only had it happen a few times so the probability is definitely orders of magnitude below 4%. I haven't noticed any correlation to whether I already have the resource or not, or how many other resources I have. I therefore see no reason to assume it is anything other than a simple probability each turn.

 

[peacenik]

A related question--do resources occassionally run out, like Civ 3?? Haven't seen it yet myself.

 

[BaneBlade]

I mine every hill in my empire, due to my strategy involving lots of workers early, and so they become not unemployed and causing civilunrest/raising crime.
4%/turn/mine simply cant be, i have maybe one ressource popping up per game, 90% of the time gold. Anybody got a suggestion why gold?!?
Bane

 

[Xarlak]

All I know is that so far in my current game, I've discovered two resources spontaneously - copper and gems. It's currently ~1400 and I've got between 10 and 15 mines total. Copper showed up fairly early (I was still researching Iron Working at the time), and gems just showed up recently. I'm glad for this, since there wasn't any copper, iron, *or* horses anywhere near my starting position. If that copper hadn't shown up right around when the AI started attacking me, I would've been in a bad spot.

 

[Thormodr]

A related question--do resources occassionally run out, like Civ 3?? Haven't seen it yet myself.

I heard that was taken out for Civ 4 because it was deemed to be one of those "unfun" gameplay things. Like pollution and city riots. I lost my only coal too many times to that in Civ 3

I had a gold and a silver appear for one city. That is my personal record. It appeared next to Madrid the Spanish capital that I conquered. I think they appeared within the space of twenty turns. Since Madrid already had four resources and was on the coast on a river it became huge for me. Production, commerce and food. It had it all. Viva la Spain. ^^

 

[cursif]

$\Assets\XML\Terrain\CIV4ImprovementInfos.xml under IMPROVEMENT_MINE there is <iDiscoverRand>10000</iDiscoverRand> so it would appear to be 1/10000 per turn per resource.

Hey, guys? Wouldn't the "Rand" in "iDiscoverRand" [as in--integer Discover Random] indicate that this chance of discovering new mineral deposits is a randomly generated? Not some inevitablity? I've always assumed that the mined square gets checked/rolled/whatever every turn to see if it sprouts minerals. While we humans like to here a 10% chance as meaning that if we try something ten times we will eventually succeed... this isn't the case when dealing with numbers and mathematical randomness. I could be wrong about how the game deals with the generation of gold, iron, etc but I stand by my statements about randomness.

 

[Xarlak]

If it's random between 1 and 10,000, then there is a 1 in 10,000 chance each turn that a resource will appear. This does *not* meant that you're assured one if you go 10,000 turns (or 5,000 turns with two mines, or whatever). Like Cursif said, mathematical randomness means that each independant check is just that - independant - it doesn't have anything to do with the results of the check before it or the check after it. It's possible to go several games without getting any resources, and it's possible to get many resources in one game.