Stardew Valley: A Complete Guide and Walkthrough
Though it is a farming sim at heart, there's a lot more to Stardew Valley than growing crops and raising animals. Players are trying to get their little farm to turn a big profit, and there are many valuable items to farm other than vegetables. Some of these include gemstones. Shiny rocks aren't just lovely and valuable; they also have uses in crafting and can make excellent gifts.
Of course, searching the mines day after day for the rarest gemstones can get to be more trouble than it's worth. That's where the 
Crystalarium comes in handy. With this miraculous gadget, players can take a single gemstone or mineral and use it to produce dozens or even hundreds more. Here's how Stardew Valley players can harness its power.
Updated January 6, 2025, by Demaris Oxman: The 1.6 update brought a lot of big changes to Stardew Valley, but it introduced some subtle balance shifts as well. A few of these have to do with high-level items like the Crystalarium, which now functions a little differently in regards to moving it and changing the stones inside. This guide has been updated to include everything players need to know in the latest iteration of the game.
Obtaining A Crystalarium
To get the Crystalarium crafting recipe, players must raise their mining skill to Level 9. The ingredients required to craft one of these items include:
- 99
Stone: This material is easy to find; simply break rocks around the farm or in the Mines using the Pickaxe. - 5
Gold Bar: Gold Ore can be mined at Level 80 and below in the mines, using the Pickaxe. Use 1 Coal to forge 5 Gold Ore into a Gold Bar at a Furnace. - 2
Iridium Bar: Iridium can be mined in Skull Cavern, or obtained daily from the Statue of Perfection. See above for how to forge ore into bars. - 1
Battery Pack: To get these crafting items, leave lightning rods outside in a thunderstorm. When hit, they'll charge up battery packs for players to collect.
Even without the recipe or the pricey, rare materials, there are still a couple of ways for players to get their hands on this valuable item.
- Community Center Bundle: A Crystalarium is rewarded to the player after completing the 25,000g Bundle in the Vault section of the Community Center. To complete this bundle, simply donate 25,000g.
- Museum: Gunther will gift the player with a Crystalarium after they donate at least 50 minerals (either Gemstones or Geode Minerals) to the Museum Collection.
Using The Crystalarium
Once built, the player can place their Crystalarium anywhere, indoors or outdoors, on the farm or off it. The Quarry is a popular place to create a crystal farm, with dozens of these machines going at once.
The Crystalarium can replicate any mineral or gemstone that the player places in it, except for Prismatic Shards. Of the potential candidates, 
Quartz takes the shortest amount of time for the Crystalarium to grow; however, Quartz doesn't sell for much, and considering how plentiful it is in the mines, players are rarely in short supply of this mineral. A 
Diamond, on the other hand, has the longest production time at 5 days. However, their incredibly high value makes the time worth it, as they are the most profitable stone to put in the Crystalarium.
To remove a Crystalarium from its current spot, strike it with the ax or pickaxe, which will return it to the player's inventory. If the Crystalarium is replicating a gem at the time, the gem will also drop. If the player wishes to change the stone in the Crystalarium, they can simply place a stone in a working Crystalarium as they would an empty one. This will replace the current stone. For example, if a Crystalarium is replicating Rubies and the player wants to use it for Diamonds, simply interact with the machine while holding a Diamond. The Ruby will pop out, and the Diamond will go into the Crystalarium.
Pop in a few precious gems and wait a few days. Soon, players will see their profits rise — and considering how many NPCs are glad to receive Diamonds as gifts, they'll be well-loved throughout Pelican Town too.
