Crystal is the resource that quietly appears in every mid-game recipe and never announces itself. It weighs 1.0, stacks to 100, and the three stations that matter — Fabricator, Chemistry Bench, Industrial Forge — want 15, 250 and 250 of it. That is 515 crystal before a single Cryopod or C4 charge, and 515 weight of cave cargo.
All values below are cached fields from ark-resources.json.
The crystal card
| Property | Value |
|---|---|
| Rarity | Uncommon |
| Weight | 1.0 |
| Stack size | 100 |
| Weight of a full stack | 100 |
| Hexagon value | 115 |
| Exchange quantity | 10 |
| Mobile purchase | 100 charges |
| Renewable | Yes |
| Refineable | No |
Crystal is a strange mineral you shape into lenses, use in electronics, or mix into explosives. — ARK Wiki
That description is unusually specific, and it maps onto the recipe data: lenses are the utility tier, electronics is the chip chain, explosives are C4. Crystal is a component, not a fuel.
The demand table
Crystal’s role becomes obvious when you list everything that asks for it:
| Recipe | Crystal | Other inputs | Level |
|---|---|---|---|
| Fabricator | 15 | 35 Ingot, 20 Paste, 50 Sparkpowder | 48 |
| Cryopod | 10 | 8 Polymer, 4 Oil, 15 Fiber, 5 Hide, 2 Ingot | 51 |
| C4 Charge | 10 | 60 Gunpowder, 5 Cementing Paste, 5 Polymer, 75 Electronics, 50 Fiber, 5 Hide | 65 |
| Chemistry Bench | 250 | 250 Ingot, 250 Cementing Paste, 250 Polymer, 250 Electronics, 100 Sparkpowder | not listed |
| Industrial Forge | 250 | 2,500 Ingot, 600 Paste, 400 Oil | 80 |
| Industrial Grinder | 2,000 | 3,200 Ingot, 800 Paste | not listed |
Two observations. First, the small recipes are cheap: 15 crystal for a Fabricator is one cave trip’s worth and the cheapest gate in the game relative to what it unlocks. Second, the large recipes are brutal: an Industrial Grinder at 2,000 crystal is twenty full stacks and 2,000 weight, which is not a trip but a project.
The 515 total for the three core stations is the number to plan around. A player who mines 200 crystal for the bench and then discovers the forge wants another 250 has made two trips where one would have done. The crafting guide sequences those stations.
Crystal against the gem alternatives
The cached data also lists three gem types, and they are not substitutes for crystal despite looking like it:
| Item | Weight | Stack | Renewable | Maps |
|---|---|---|---|---|
| Crystal | 1.0 | 100 | Yes | all |
| Blue Gem | 0.5 | 100 | No | Aberration, Valguero, Genesis Part 1, Crystal Isles, Lost Island |
| Green Gem | 0.5 | 100 | No | Aberration, Valguero, Genesis Part 1, Crystal Isles, Genesis Part 2 |
| Red Gem | 0.5 | 100 | No | Aberration, Valguero, Genesis Part 1, Crystal Isles |
The gems are half the weight and half the stack weight (50 per stack), but they are not renewable and they are map-locked. They appear in the Element charge-node recipe and in primitive tools and saddles, not in the station builds that drive crystal demand. If you are on Aberration, gems are your local currency; if you are on The Island, they do not exist.
There is also Primal Crystal, at 1.0 weight with a stack of 1 and a spoil timer of 2,700 seconds, limited to Crystal Isles. A single-item stack for a crystal variant is a strong hint that it behaves like a trophy rather than a resource.
Weight and slot maths for a cave run
Crystal is dense, and that has consequences:
| Load | Crystal | Weight | Slots |
|---|---|---|---|
| 2 stacks | 200 | 200 | 2 |
| 5 stacks | 500 | 500 | 5 |
| 10 stacks | 1,000 | 1,000 | 10 |
Five hundred crystal is only five slots — the slot cost is trivial. The weight is what stops you: 500 weight is a full load for most mid-game carriers, and 1,000 is beyond them.
Compare that with obsidian, which has identical weight and stack values. A cave run that fills both is limited by the same budget, so the decision is purely which recipe is waiting at home. The obsidian page covers the other half.
The efficient cave load, then, is crystal and obsidian in the quantities your next two recipes need, plus free cargo: pearls at 0.02 and rare mushrooms at 0.2 cost almost nothing per slot and fill the gaps. The silica pearl page covers the dive; mushrooms come from the same caves, as the mushroom page explains.
Harvesting that keeps the trip short
The data does not publish per-node yields, so the advice is structural: crystal is a rock-type node, which means the same harvesters that handle metal handle it, and the same carriers move it. Three habits make the difference:
- Mine in recipe-sized batches. 15 for the Fabricator, 250 for the bench, 250 for the forge. Mining 200 “because it looks like a lot” is how you end up short twice.
- Bring the harvester, not the pick. The Ankylosaurus clears a node cluster in a fraction of the time, and the gathering guide lists the alternatives by resource.
- Leave the second trip for the pearls. Because pearls weigh nothing, the only reason to return to a cave is crystal or obsidian. Combine them.
The exploration guide covers cave routing and loadouts, and the base building guide covers storing dense materials near the station that consumes them.
Hexagons: crystal is a bad trade
At 115 hexagons with an exchange quantity of 10, crystal is worth less than silica pearls (125) and much less than a metal ingot (195). Converting crystal to hexagons is almost always the wrong move: a Chemistry Bench alone consumes 250 crystal — roughly 17 Fabricators’ worth — and that crystal is worth far more built than traded.
The one case where the hexagon value matters is Genesis, where missions pay in hexagons and the shop sells materials. Even there, 115 for a unit that weighs 1.0 and takes a cave trip to obtain is a price that reflects convenience, not value. The resources strategy page covers when to buy and when to mine.