Gems are rare resources that can be obtained randomly from Mining. You will only start finding gems after finishing the Let The Mining Begin quest, however, the Miner does not have to be mining for you to find gems. This means that unlike Ores and Geodes, running more Mining Machines or Miners will not increase your chance at finding gems. In fact, nothing in the game can boost your gem luck rate; it is purely luck.
|Gem||Rate (Ticks)||Rate (Days)||Avg Gems / 100 Days||Sell to NPC Shop|
Gems (except for Blood Diamonds) can be used to upgrade all Tools (except the Wrench), to provide increased rates (e.g., Trowel, Shovel, Axe, Chainsaw), decreased Stardust costs (e.g., Pickaxe and Hammer), or otherwise enhanced effects for that tool. Gems must be "socketed" in a tool in ascending order, from Sapphire to Emerald to Ruby to Diamond. Because they provide permanent buffs, it is generally advised to use all gems to upgrade your tools first, before using them for other purposes. It is generally advised to first upgrade your Brewing Kit, Axe, and Fishing Tools.
Treasure Chest Keys
Gems can be used to craft Treasure Chest Keys, which are used to obtain loot from Treasure Chests. Higher tier gems will provide more rolls on the loot table when opening the chest. Because of the relative rarity of obtaining Treasure Maps, it is generally advised to use at least an Emerald Key when opening chests, if not higher.
Gem Stardust Potions
The Sapphire Stardust Potion, Emerald Stardust Potion, and Ruby Stardust Potion can be poured on a Sapphire, Emerald, and Ruby respectively, consuming it and yielding Stardust. This can be a good alternative to selling unneeded Sapphires or Emeralds. The Stardust yielded is based off your Brewing level.
The Sapphire Glass Hand, Emerald Glass Hand, Ruby Glass Hand, and Diamond Glass Hand are all items that can be crafted (just once) to be sold to the Museum, and require one Sapphire, Emerald, Ruby, or Diamond respectively, also requiring 20 Glass. The sale price to the Museum is usually lower than the cost of the gem and the glass on the Market, so it's more of an achievement than a way to generate coins.
Gems can be sold either to the NPC Shop or the Player Market. Lower tier gems (Sapphires and Emeralds) generally only sell for slightly above the NPC Shop on the Player Market, but Rubies and Diamonds sell for significantly more on the Market.
|Sapphire • Emerald • Ruby • Diamond • Blood Diamond|
|Mechanics||Coins • Energy • Fight Points • Heat • Oil • Stardust|
|Items||Bones • Feathers • Foods • Leaves • Logs • Seeds|
|Mining & Smelting||Bars • Charcoal • Gems • Geodes • Lava • Ores • Sand|