With 160 update just around the corner here is an analysis of the outer city (names for everything may vary depending on translation by Batheo):
There are 12 buildings for outer city (Lv requirements are for Collecting field building lvl):
1) Collecting field (starting building)- primary building of outer city, determines level cap for all outer city buildings
2) Worker camp (starting building)- increases worker cap and number of workers
3) Gem warehouse (starting building)- increases maximum ore reserve (think silver vault/granary in inner city)
4) Gem Mines (Gem Mine 1 at Lv 110, Gem Mine 2 at Lv 130, Gem Mine 3 at Lv. 150)- Increase gem output (think training grounds in inner city)
5) Prospector building (aLv 150)- increases crit rate of gem collection
6) Main Officee (Lv 140)- reduces cost of building upgrades for outer city
7) Garrison camp (Lv 120)- increases minimum production from gem mine
8) Supervision building (Lv 160)- percentage increase in ore collection
9) Carpenter office (Lv 120)- reduce outer city building CD
10) Refine Studio (Lv 160)- increase the success rate of gambling stones
11) Refine Sorting Workshop (Lv 130)- refines gems
12) Refine Craftsman building (Lv 140)- reduces gem refining CD
Outer city buildings share a building CD with the inner city; however, they have substantially longer CDs per upgrade. what will separate players apart is the order of building upgrades, unless you reduce CDs with gold (however this very costly since CDs will rise upwards of 1-2 days). There are a couple of upgrade orders (large degree of overlap between them) that are considered the most efficient.
Outer city buildings cost ore to upgrade rather than drachs. The conversion rate between ore to gems is 1000 to 1. This is a continuous system and done automatically by the system depending on whether you are in inner city or outer city interface. In the inner city view, you will see everything as normal (i.e. 596 gems in your inventory). Once you switch to outer city view, you will see available ore (i.e. 596,000 ores). Gem numbers will be rounded to whole number. Ore amount is capped by your gem warehouse (I believe initial inventory cap is 100k?), where you can exceed but won't get benefits of production. The estimated total cost for 1 to 160 of all 12 outer city buildings is 50k gems or 50 mil raw stones.
"Gambling ore" is part of the "diamonds in the rough" system and involves the last 3 buildings on the list... let's just say it's another way to burn gold. It's a largely criticized system. The basic idea is that the refine studio finds "diamonds" that range from white to purple (like all other equipment), which must be cut (lots of complaints about success rate where 92% isn't really 92%, blah, blah, blah). There is an auction system attached as well to selling the stones if you don't want to burn gold. (Have to read a little more into the system, will update with details later)
There was also huge bug issue with diamonds in the rough that resulted in massive account bans for exploitation.
There are 12 buildings for outer city (Lv requirements are for Collecting field building lvl):
1) Collecting field (starting building)- primary building of outer city, determines level cap for all outer city buildings
2) Worker camp (starting building)- increases worker cap and number of workers
3) Gem warehouse (starting building)- increases maximum ore reserve (think silver vault/granary in inner city)
4) Gem Mines (Gem Mine 1 at Lv 110, Gem Mine 2 at Lv 130, Gem Mine 3 at Lv. 150)- Increase gem output (think training grounds in inner city)
5) Prospector building (aLv 150)- increases crit rate of gem collection
6) Main Officee (Lv 140)- reduces cost of building upgrades for outer city
7) Garrison camp (Lv 120)- increases minimum production from gem mine
8) Supervision building (Lv 160)- percentage increase in ore collection
9) Carpenter office (Lv 120)- reduce outer city building CD
10) Refine Studio (Lv 160)- increase the success rate of gambling stones
11) Refine Sorting Workshop (Lv 130)- refines gems
12) Refine Craftsman building (Lv 140)- reduces gem refining CD
Outer city buildings share a building CD with the inner city; however, they have substantially longer CDs per upgrade. what will separate players apart is the order of building upgrades, unless you reduce CDs with gold (however this very costly since CDs will rise upwards of 1-2 days). There are a couple of upgrade orders (large degree of overlap between them) that are considered the most efficient.
Outer city buildings cost ore to upgrade rather than drachs. The conversion rate between ore to gems is 1000 to 1. This is a continuous system and done automatically by the system depending on whether you are in inner city or outer city interface. In the inner city view, you will see everything as normal (i.e. 596 gems in your inventory). Once you switch to outer city view, you will see available ore (i.e. 596,000 ores). Gem numbers will be rounded to whole number. Ore amount is capped by your gem warehouse (I believe initial inventory cap is 100k?), where you can exceed but won't get benefits of production. The estimated total cost for 1 to 160 of all 12 outer city buildings is 50k gems or 50 mil raw stones.
"Gambling ore" is part of the "diamonds in the rough" system and involves the last 3 buildings on the list... let's just say it's another way to burn gold. It's a largely criticized system. The basic idea is that the refine studio finds "diamonds" that range from white to purple (like all other equipment), which must be cut (lots of complaints about success rate where 92% isn't really 92%, blah, blah, blah). There is an auction system attached as well to selling the stones if you don't want to burn gold. (Have to read a little more into the system, will update with details later)
There was also huge bug issue with diamonds in the rough that resulted in massive account bans for exploitation.