It replicates any inserted mineral (other than the Prismatic Shard), making gathering hard-to-farm gems and geode minerals much easier. While the Diamond is a great gem to duplicate because of its wide range of uses, there’s plenty of options that can fit your playstyle, whether that’s maximizing profit, friendship points, or decal.
Strategies For Using the Crystalarium
The following list, divided into three categories for different uses, highlights some gems and minerals that are worth replicating. This is not an exhaustive list, but a subjective rating based on practicality. Quick Tip: if you want to replace the gem that’s being duplicated, make sure to first remove the Crystalarium with a tool to get the original gem back. Inserting a new gem immediately will permanently remove the previous gem.
Money-Making
In terms of profit, Diamonds are objectively the best item to duplicate, as they provide the best gold (750g) to time (5 days) ratio compared to all other gems Fire Quartz can also be quite lucrative; not because of its own sell price, but because of what it can be used for: Slime Egg Presses (which produce Slime Eggs that sell for 1,000g up to 8,000g), and Lava Eel fishing ponds (which produce lava eels worth 700g and aged lava roe that have a base sell price of 760g) Earth crystals are a crafting component for Mayonnaise Machines, a great early-game money-maker
Gifts
Note: Diamonds are universally liked by all villagers. Except for the Prismatic Shard, all other gems are universally liked by everyone other than the three townsfolk who dislike them: Leah, Linus, and Pierre.
Other Uses
Diamonds can be used for geode crushers, fairy dust, and forging—three new end-game mechanics that were recently added in the 1.15 update Five pieces of quartz can be exchanged for one bomb at the Desert Trader. They can be smelted into refined quartz, which can be used to craft quality sprinklers and crystal paths Marble is hard to farm from frozen geodes, but with the Crystalarium, having at least one piece can allow you to make as many Marble Braziers as you need
What are you waiting for, then? Those gems won’t replicate themselves!
