The Vault - Fallout Wiki

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The Vault - Fallout Wiki
The Vault - Fallout Wiki
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This is a lore summary, presenting intradiegetic or in-universe information about the subject. For game characteristics and similar data, consult the table on the right.
Game-specific articles
Fallout 76Ultracite (Fallout 76)
Ultracite ore

An ultracite vein.

F76 Ultracite ore.png

Ultracite is a unique material endemic to Appalachia, with properties as unique as they are dangerous.


Ultracite is a unique, radioactive glass-like material discovered by Atomic Mining Services beneath the soil of Appalachia. Although its origins mystified AMS scientists, its properties did not: Ultracite was an incredibly potent source of energy, to the point on near inexhaustibility. Although its potency could slag reactors and cause meltdowns, when properly handled it could supply enough power to keep industrial-grade machinery working for decades. AMS fully believed it to be the future fuel source for the entire United States - and with them in control of the supply, their hegemony on the market.[1] At first, AMS started locally, powering Watoga and leasing their technology to the two major corporations on the mining market in Appalachia: Hornwright Industrial Co. and Garrahan Mining Co., as well as the energy conglomerate Poseidon Energy. The contracts came with strings attached: To power the Excavator power armor, Garrahan had to make a decade-long commitment to AMS technology.[2]

While they secured a dominant position on the market, AMS also worked to remove the obstacles to widespread adoption of ultracite nationwide: Depleted ultracite played havoc with the regular material, resulting in a corrosive reaction melting both materials, necessitating extreme care in separating and containing the two materials. However, that complication was only second to the biggest one: AMS did not understand the creation process for ultracite. This led to situations where shafts marked as failure could suddenly develop veins of ultracite, as was the case with mine shaft no. 9 near the town of Welch. The ultracite vein rapidly developed, emerging not just in the shaft, but inside the town.[3] In order to maintain their monopoly, AMS quickly secured property rights - on within twelve hours - and moved in to force everyone in the town off of their property. Unsurprisingly, the move radicalized the already angry miners.[4]

Eventually, it was determined that ultracite was the result of ore responding to extreme environmental factors. To replicate them, AMS decided to perform underground nuclear tests in order to create artificial ultracite. The "radioactive glass", as contractors came to call it, could be reliably obtained that way and made the expense entirely worthwhile.[5]


Ultracite is a high-level crafting material in Fallout 76, used to manufacture high-end power armor and modifications for late-game equipment.


  1. Glassed cavern terminals: "If you have any doubts about what we're doing here, then I want Doctor Ector to give you a demonstration of the generator technology his team is working on.
    A chunk of that Ultracite is still powering that generator. It's going to power this whole mine once they're done. Do the math. Hell, make Doctor Ector do the math FOR you.
    Ultracite is going to be the future fuel source for this entire country. We're not stopping over a few protestors. Let the politicians worry about that."
  2. Garrahan Mining Headquarters terminals: "After a few slagged reactors and a near meltdown, we finally have Ultracite powering the Excavator. Vivian wasn't exactly thrilled making the ten-year commitment AMS was demanding for their patented ore, but it had exactly the power output and radiation signature we needed. All that remains now is mounting the Ultracite-fired reactor into the chassis and see if we can get this beast to move some rock."
  3. AMS Corporate Headquarters terminals: "*Energy production from Ultracite continues to exceed expectations.
    *Depleted Ultracite disposal continues to be a problem. Contact with non-depleted Ultracite causes a corrosive reaction that melts both materials. Care has to be taken to contain all depleted Ultracite material after use to avoid contamination.
    *No explanation on why we failed to detect Ultracite in Mine Shaft No. 9. All previous measures ruled that site a failure. The sudden development of Ultracite there continues to confound all our previous assumptions.
    *The vein in No. 9 extending/bursting into the town of Welch has also had unintended consequences of a more political nature. Our friends in the state capitol are asking more questions at a time when we need to focus.
    *Answers on how Ultracite is created continues to be a top priority if we're ever going to take production to the national level."
  4. The Rusty Pick terminals: "Word came in from Welch that a bunch of veins of Ultracite peeked out their nasty mugs after a ground-shaker two days ago. Lost half of my team when they ran home to start grabbing whatever they could. Not even twelve hours after the frenzy, AMS goon squads moved in ready to demolish houses to get at "their property." People were none too please. That's when shooting broke out. I've called for another meeting with O'Conner's group. We need to act now, before AMS and Hornwright erases us from the map."
  5. Bad news: "I don't like it, Sam. Not one bit. They want to drop a nuke down here? And what for again? To get some kind of radioactive glass out? What'd that labcoat call it, "Ultracite?" You and I both know the main shaft is barely holding together. This is bad news. Don't you let them do it!"