Gem Mine mining a Gem
The Gem Mine is a feature found on the World Map that produces Gems for the player over different periods of time. Every section of the map contains one gem map, totaling 7 Gem Mines that can be unlocked.
In update 2.10, a "collect all gems" button was added, making harvesting the gems for gold much easier.
The guild Gem Mine bonus, which unlocks at level 16, gives a value bonus to all gems mined. The bonus starts at +400 for level 16 guilds and maxes out at +1000 for level 20 guilds.
Gem Mines produce gems over set periods of time. The further through the World Map the player travels, the longer the Gem Mines take to mine gems, and the higher in value the gems mined become. Unlike the Gold Mine, the Gem Mines cannot be upgraded to produce higher level gems, or increase mining speed.
The gems mined are of random colors, so one may collect gems until 3 mines are a color gem they want, then merge them for a potion.