"Collects minerals like stone, iron, and gold from surrounding mineral seams."
The Quarry mines resources in a 6x6 tiles field, with the quarry in a 2x2 field in the center, which needs to be free space adjacent to the minerals, not the mineral tiles themselves.
Other Quarries cannot be placed so that any already mined resource tile overlaps. However, Quarries can be placed closer if they are mining only separate resources.
Each Stone or Iron resource tile a Quarry uses contributes .5 resources/cycle, with the final production being rounded up; a Quarry will thus produce the same resource amount for one and two tiles. Gold resource tiles are mined in the same way, but produce 10 gold per tile, which will be added to gold income straightly.
Can be upgraded to an Advanced Quarry.
The time to profit on such a quarry, assuming all resources would be sold, neglecting the value of the wood, and not counting construction time, is represented in the following table:
| Stone Production Per Cycle ⇅ | 1 Market ⇅ | 2 Markets ⇅ | 3 Markets ⇅ |
|---|---|---|---|
| 1 Stone | Never | Never | Never |
| 2 Stone | Never | Never | Never |
| 3 Stone | Never | 6000 hours (250 days!) | 864 hours (36 days) |
| 4 Stone | Never | 752 hours (~31 days) | 375 hours (~16 days) |
| 5 Stone | 1200 hours (50 days) | 400 hours (~17 days) | 240 hours (10 days) |
| 6 Stone | 600 hours (25 days) | 272 hours (~11 days) | 184 hours (~8 days) |
| 7 Stone | 400 hours (~17 days) | 208 hours (~9 days) | 144 hours (6 days) |
| 8 Stone | 300 hours (~13 days) | 168 hours (7 days) | 120 hours (5 days) |
| 9 Stone | 240 hours (10 days) | 144 hours (6 days) | 104 hours (~4 days) |
| 10 Stone | 200 hours (~8 days) | 120 hours (5 days) | 88 hours (~4 days) |
| Iron Production Per Cycle ⇅ | 1 Market ⇅ | 2 Markets ⇅ | 3 Markets ⇅ |
|---|---|---|---|
| 1 Iron | Never | Never | Never |
| 2 Iron | Never | 752 hours (~31 days) | 376 hours (~16 days) |
| 3 Iron | 600 hours (25 days) | 280 hours (~12 days) | 184 hours (~8 days) |
| 4 Iron | 304 hours (~13 days) | 168 hours (7 days) | 120 hours (5 days) |
| 5 Iron | 200 hours (~8 days) | 120 hours (5 days) | 88 hours (~4 days) |
| 6 Iron | 152 hours (~6 days) | 96 hours (4 days) | 72 hours (3 days) |
| 7 Iron | 120 hours (5 days) | 80 hours (~3 days) | 64 hours (~3 days) |
| 8 Iron | 104 hours (~4 days) | 72 hours (3 days) | 56 hours (~2 days) |
| 9 Iron | 88 hours (~4 days) | 64 hours (~3 days) | 48 hours (2 days) |
| 10 Iron | 80 hours (~3 days) | 56 hours (~2 days) | 40 hours (~2 days) |
Of course, less profitable quarries may still need to be built in order to fund construction, but the above tables should give you an idea of whether it is worth building a quarry if your current construction needs are already met. Also, the table may give you some idea why experienced players tend to only want to build quarries on 5 Stone or better, but are generally happy to take even a 2 or 3 Iron.
Because iron is exactly twice as valuable as stone, if a Quarry is producing a mixed number of resources - for example 5 stone and 2 iron - then it is as profitable as a stone quarry producing the same amount of stone plus 2 stone for each iron, or in this example 9 stone. Thus such quarries can be highly desirable and profitable indeed.
Gold quarries of any size are profitable on paper, but in practice owing to the worker, energy, and space considerations generally at least 2-3 gold tiles are preferred.