Gold Mine

Level	Hitpoints	Upgrade cost	Upgrade time	Town Hall
1	75	150	5s	1
2	150	300	15s	2
3	300	700	1m	2
4	400	1,400	2m	2
5	500	3,000	5m	3
6	550	7,000	15m	3
7	600	14,000	30m	4
8	660	28,000	1h	4
9	720	56,000	1h 30m	5
10	780	75,000	2h	5
11	860	85,000	3h	7
12	960	170,000	4h	8
13	1,080	400,000	5h	10
14	1,180	800,000	6h	11
15	1,280	1,200,000	10h	12
16	1,350	2,000,000	1d	14
17Max at TH18	1,400	8,000,000	2d	16

From level 1: 12.8M elixir and 4d 9h to max at Town Hall 18.

Charge	Hitpoints	Damage per second	Cost	Time
1	–	–	1,700,000	2d
2	–	–	1,500,000	3d
3	+50	–	1,300,000	4d

All 3 charges: +50 hitpoints, for 4.5M elixir and 9d.