Here are the donation amounts as of Dec. 31, 2013 They are all per month basis.
Level 15 and under: 800 resources, 400 coins
Level 16 - 17: 1200 resources, 1000 coins
Level 18 - 19 : 2700 resources, 3500 coins
Level 20 - 24: 6200 resources, 6000 coins
Level 25 - 35: 9600 resources, 8000 coins, 10 rubies
Level 36 - 39: 12000 resources, 10000 coins, 10 rubies
Level 40+: 16000 resources, 15000 coins, 15 rubies
All donations are due on the 15th of every month
Mandatory donations are currently being revised, they will not be mandatory until further notice.
Level 15 and under: 800 resources, 400 coins
Level 16 - 17: 1200 resources, 1000 coins
Level 18 - 19 : 2700 resources, 3500 coins
Level 20 - 24: 6200 resources, 6000 coins
Level 25 - 35: 9600 resources, 8000 coins, 10 rubies
Level 36 - 39: 12000 resources, 10000 coins, 10 rubies
Level 40+: 16000 resources, 15000 coins, 15 rubies
All donations are due on the 15th of every month
Mandatory donations are currently being revised, they will not be mandatory until further notice.