Hycroft Mining Holding Corporation

Good morning or good evening, depending on where in the world you're signing in from today. I did see it was a very international audience, so I really do appreciate you joining us today. Today I've got on Highcraft Mining's VP of Exploration, Alex Davidson. CEO Diane Garrett had a last-minute flight and is unfortunately unable to join us today, but we're all technical, so Alex is actually the perfect guy to talk to, so I'm glad that I've got you. How are you today so far, Alex?

Good, good. Thanks for having me again. I appreciate it. It's always a pleasure to talk with you.

Awesome. So here's how today's going to work. I've got some questions for Alex about the most recent press release. So we'll really get into the technical details for the geos and tech guys in the crowd. This should be a very interesting event because Alex always has a great perspective on the geology of the High Craft project. I will say, if you have any corporate, company, finance, et cetera questions that usually Diane would tackle, please feel free to share them. We're just not going to get to them today, but I'm going to share the transcript directly with Diane and her team, and we'll make sure that they get back to you as soon as possible. So still feel free to ask those questions. We're just probably not going to get to them today. In that vein, it is an interactive event. There's a chat button in the bottom right. And if you ask stuff that Alex and I can tackle there, I'll be thrilled to get to it right after my questions. I know a lot of you submitted questions over email, so I'm going to get to as many of those today as we can. There's some interesting ones, so I'll make sure that we pose them. Otherwise, last piece of housekeeping. This event is recorded, and replay will be available probably early this afternoon, Eastern time. So I'll make sure it gets in all of your inboxes as soon as possible. That's it for my housekeeping. Let's get into the proteins. Alex, I'm going to grill you for a few minutes if you don't mind. Yeah, go for it. Awesome. So from the PR, beyond what we see in the drill results, what specific mineral assemblages or alteration halos are you observing that helps you classify brimstone as that intermediate sulfidation system?

Yeah, that's a good one. And straight up, the things that we've seen in brimstone, as I've talked about in previous and again in this most recent one, we've done petrographic studies, we've deployed a program for geochemical sampling, and there's some real standout things that distinguish brimstone from everything else that we see at Highcroft. From the petrography, We know that we have silver minerals called, you know, nominate, Argento tetrahedrite, selenostephanite, and there's a slew of others as well. But those are the big ones for us. And those in particular, and we verified this with our geochemistry. So the way this works is You do the petrography, and that tells you specifically what kinds of minerals you have at play. And you use your geochemistry. That helps you with your geochemistry. So it gives you a ratio to look for specifically. You plug in the ratios from the mineralogy, from that petrography, and then with the geochemistry, a much broader scale to look at. you can look at everything across your deposit and know that there's a real tight relationship with those ratios that suggest or tells you that those are the minerals that you have. So what's specifically about those are it's the presence of copper, lead, zinc, selenium. Those are strong characteristics of an intermediate sulfidation system. Those things just don't exist in an amagmatic epithermal system, which Highcroft has previously been known. So this is clearly a different beast than what we're working. And I want to emphasize that this is really exciting for us because this tells us that there's something much larger at play at Highcroft than what has ever been known before. So this gives us a lot of new opportunities across the property that just simply didn't exist before. So it is a real big paradigm shift for us.

I appreciate that. I find that really interesting. One thing I'm curious about is the structural orientations that you're seeing that are most associated with the highest grade silver intercepts. How does that influence your future drill targeting?

So, yeah. I guess let's first start off with what the exploration program had in mind. So in particular, Brimstone, what we were trying to achieve, there's two real objectives that we needed to achieve with the brimstone target. We knew it was a high grade target, but fundamentally we didn't understand the structural framework of what was going on there. So first and foremost, in order to understand the deposit, you need to understand the structure and what's driving everything. And so what we did to help us do that is we used a, a tool it's called ATV the full sorry acronyms ATV stands for acoustic televiewer and what that does is it's a tool you send down a mole and it gives you real world orientation of your veins and structure and so on and so forth so we use that and it taught us quite a bit about uh what's happening at brimstone i think one of the one of the things that the major thing that we learned there are the veins are not associated with eastfall again paradigm shift for us the eastfall has always been considered to be if i'm uh showing you that the plane of the eastfall fluids have always been that's always been the main control of uh fluid coming up What we know is from the televiewer data that the veins are much lower angle and not associated with that. That adds another level of complication to things for us because now we know that brimstone is also been offset by other east fault like structures. So that's not a bad thing. It just tells us that things have moved and now we kind of have good understanding of how to adjust our program going forward with all those ratings down dip.

That's great. It's good to have that direction.

Yeah. The second part of the function was to grow that part of the deposit. So each hole was designed, one, to tell us about structure, and two, grow the deposit. 13 or so holes that we drilled in brimstone proper, we had 10 holes that were just outrageously good grades. There are a few in there that are just unbelievable. In fact, 6018, which is our last press release we did earlier in 2025, beginning of the year, had an intercept of over 80,000 grams per ton, which is just amazing. In fact, I saw on LinkedIn just recently, there's a company who does gold intercepts, best gold intercepts in drilling and best silver. And for the first quarter of 2025, Highcroft had the highest intercept in the world or wherever you're taking the measurements. It was really, really interesting to see.

I saw that. That's always good to see, obviously. Yeah. Actually, I'm going to go to one question from the chat here. GT asks, how many core samples from 2024 are left to be reported on?

None. Everything in this last press release cleaned up the 2024 drilling.

Perfect. One, could you discuss any geochemical zonation patterns you're seeing across the property? And what do those reveal about the overall architecture of the system you're seeing?

You're asking really good questions, Romeo. I got to ask, did you get a geology degree since last time we talked?

That's unfortunately still political science, but I try to read as much as I can.

OK. So from the drill results, there are a few things that really help us understand. Again, staying specific to brimstone, one of the things that we see are that we look at, and we'll start there, is gold to silver ratios. So the silver to gold ratios are extraordinarily high in brimstone. They're plus 1600 to one. That means 1600 ounces to one of silver to one ounce of gold. So that is a key thing. That is also a key thing that differentiates brimstone from pretty much everything else. And additionally, again, we'll say it over and over again, the presence of copper, lead, zinc, manganese, anemone, selenium, there's a number of things that go to that intermediate sulfidation type system that is brimstone. Comparatively speaking, when we move over to, say, vortex, the silver to gold ratio changes. It's more on the order of 600 to 1. We see less selenium, less anemone, very, very low copper, very low lead zinc. It's not that they're nonexistent. It's just that they're not a major player in those minerals that are there, if that makes sense.

No, no, appreciate that for sure.

So that's how we look at geochemical zonation, if you will, across the property.

Great. No, thank you. One thing I want to talk about with the, you know, when you're thinking about developing the high grade zones at Brimstone, what drilling or metallurgical challenges do you anticipate compared to the historic heap leach operation?

So drilling, Drilling always has complications to it, and it's dependent on, you know, any variety of things can go wrong when you're drilling. That's kind of a given. It's why I have the drill services people that I have in place. They are experts in those fields, and they manage that very, very effectively. My drill services guy, Jim Stoss, kudos to him. He's got 40 some odd years, 40 plus years in drilling and can handle those situations very effectively. And last year really was, it was learning. Every single deposit is different, just given. Everything about it is different in every way. So what was fun about watching Jim is learning, adapting, and taking his knowledge and applying it to the next role. Uh, and at the end, you know, we had a very successful year, really. We really did have a great year on, on drug. So, uh, metallurgical challenges, um, you know, we're, we're still really working through our, uh, metallurgical program. We're still particularly on the high grade. We've got all of our, uh, um, geochemistry back and we're done all the analysis on that. So now it's building a sample collection for metallurgy off of those drills. So I don't know if you know, but what you do, you drill a hole, we take half of that core and we sample that half and we get gold, silver, and a suite of 64 element geochemistry off of that. And that tells us, you know how how to go about making our metallurgical samples so so that's what we're doing right now putting that together this is specific for for the high grade so the good things that we know uh right off the bat is um uh there aren't any big things out there that's going to affect uh crushing grinding flotation all those sorts of things that will be handled quite well with what we know. That's not a problem. And it's the work on the back end that we're going through right now, trying to figure out pressure oxidation or roasting and all that sort of stuff. So all that work is going on, and we should have those answers out to the public in the second half of 2025.

Awesome. No, that's great. Very helpful. Um, I'm going to take a couple of questions from the chat. There's one, um, I get this in the chat. People send it on email. You see it on social media. It's some variation of when does the highcraft start mining? Uh, it's like when, uh, when, when does extraction begin? So I'll throw it to you just for a quick lesson of folks on, on how this process works.

Yeah. Yeah. That's, that's kind of a common question. We've had that a few times, uh, on, on these webinars. Um, and, and quite honestly, the, The work that we're doing right now will get us there. You have to do ore body knowledge. You have to do the geology. You have to understand mineralization. You have to understand the controls to mineralization. You have to do the geology work. That feeds into understanding the metallurgy. You have to do all the metallurgical work and all of that testing. And it sounds like a function of science and an academic exercise, but it isn't. You have to do those things in order to understand how to mine this property. You have to go through all those steps to understand how to build your mill. You have to build your mill before you start mining. So all those things play into that. Any company that is a good steward of their ore body will do that work up front before they just go mine. And that's what we're doing.

Yeah, I think that's great. And any variations of that question we see, I always like to have you answer it just so people can understand what the process is like of setting up a real mine to do it responsibly and well. So I'm glad we can tackle that. There's one question that Rock had in the chat. He notes, as you did, that there's many minerals at Brimstone, that it's very mineral rich. He's curious how that impacts extraction and if it might result in lower extraction rates for some of those minerals just because they're all packed together.

um no i i there there isn't yeah there isn't anything in particular out there that we believe is going to give us uh metallurgical difficulties um and and again kind of coming back to your earlier question uh We're doing the metallurgy work right now in order to understand how to unlock it. You know, all our bodies are complicated. Metallurgy is a very complicated thing. They're not unsolvable. We've been doing it for a long time. It's, you know, us specifically, you know, we're different. We have different things that have complication. but they're not unsolvable. And we will get to a point to fully understand how to recover those minerals.

Perfect. One thing I'm curious about, how do fluid inclusion studies or other detailed analytical work factor into your interpretation of the deposits genesis and its potential at depth?

Are you sure you didn't get a geology degree? Fluid inclusion is pretty specific. That's a really good question. The straight up answer, we haven't done fluid inclusion work yet. And fluid inclusion work is something that we are going to do. So the audience understands what that does. It's extremely helpful in us understanding the perigenesis of deposits. Geology is a complicated thing in that it's not just a function of three dimensions. There's a fourth dimension in there of time. So we're constantly dealing with gaps in times, offsets, what came first. And those sorts of understanding that helps us understand how to target, how to mine, all of that. It's a big part of it. fluid inclusion work is something that we're going to include into, uh, into our, our next exploration, uh, phase of exploration. It's a critical part. It's another tool that really helps us get that fourth dimension of understanding, uh, in there. So it's a, it's a critical part of what we'll do. So other things that we've done, I've talked about them at nauseam, it's hyperspectral, geochemistry, petrography. There's a whole litany of other analytical work that all work together. Fluid inclusions is just another level of tying that work together. There isn't just one sort of thing that you can do that's that silver bullet aha. It solves everything. It just doesn't work that way. Everything works in concert together. You do geophysics, and that gives you a broad scale of how things would look in the subsurface. You do geochemistry. You do, you know, the more physical, actual drill in a core hole. That helps you understand structure. You do mapping. That ties your surface structure to your underground drill holes, right? All of it works together in concert.

Great. I want to get onto the manganese target because there were a lot of questions about it and I certainly had some questions myself. I'm curious what specific evidence you have that suggests connectivity between the manganese target and the vortex brimstone systems beyond just the spatial proximity.

So let's talk a little bit about manganese First, let's understand how the target came to be. This is a process over the last several months, you know, throughout the whole 2024 mapping exercises to the east of the pit where manganese sits. There's no drilling out there. There's no information, but we had indicators that there was something going on out there. So, excuse me, we went through a robust mapping exercise. I have a consultant, Jeff Nichols, who we worked with for a long time back in my Newmont days and so on and so forth. He's just an excellent exploration geologist. He spent a lot of time in the field mapping and sampling, looking at soil samples that had been completed out in the area in the past and understanding that manganese is a major player out there. It's anomalous. And that's really what kind of started building that concept. And we started tying that, those structures into the pit, we could clearly see that there's a strong relationship. Those structures are continuous. They sampled similarly. The results that we got back from those similars all show high silver grades and high manganese and so on and so forth. So the drill hole, 6015 that we put in this year, was a conceptual target trying to understand those structures. And fortunately, right off the bat, we had excellent results off of that. And so here's the problem is manganese is understood for mapping in one drill hole. So I can't come out and say that manganese is absolutely tied to brimstone or absolutely tied to vortex yeah they're spatially they're spatially close to one another but we don't know enough about the system to really know how they're related or if they're related I think that's a key factor in Highcroft is now we know that there's multiple events that have created the Highcroft deposit, right? So we're trying to understand what that is. Manganese has some structural similarities to what we see at Vortex, but that doesn't necessarily mean they're the same system. So, you know, it has the big thing that we've seen so far with our one drill hole, is that it's mineralization on low angle structure at the intersection of a high angle structure. So if you look at lower angle structure, high angle structure, it's this intersection right here that we're seeing that mineralization. And frankly, there's a lot of work to be done to really understand what's going on. So we're building those targets now on how to move forward. Conversely speaking, brimstone is vein-driven, structurally controlled, and it has extremely high silver to gold ratios. Vortex is different. Again, it's entirely in low angle structures. It's a broader zone, very minor vein. We don't really see a lot of the similar, we don't see a lot of the brimstone type veins they're there but they're a minor component of of what makes brimstone that and the silver gold ratio is again different we just don't have enough data to really define how manganese is related to all of those stones but it's exciting it's really exciting because it is east of what is known to be high craft it's on a thousand it's fully a thousand feet east of of uh the Eastpaw, which was considered to be the maximum limit of the Hycroft system historically.

Fun finding the new. That's always exciting. Now, there's one question from the chat, and I hate asking you over and over again when you start mining, but I just want to be as helpful to everybody in the room as possible. So Mike from the chat asks, are the current results of the drilling that you just announced significant enough to start mining right now? I just want to explain to folks in the room what the process is from here.

Yeah, I guess to be clear, we'll just talk a little bit about the 2024 exploration program. It was a small program relatively compared to what we've done in the past. It's a very small program, what I've done in the past. It isn't enough to get us to mining right now. The design of that program was to help us understand structures designed to help us grow that deposit a little bit. It's designed to help us know what to do for the next steps. It's a giant step forward in understanding what Highcroft is and what it can be, but not quite enough to get us right to mining right now. It's very exciting for sure. It's growing. There's still a fair amount of work to do before we get to mining.

Awesome. I appreciate that transparency very much. I'm curious, beyond IP, what other geophysical methods could you employ to better target those high-grade zones? And then why might you pick one method over the other?

Yeah. First, let's understand IP. IP stands for induced polarity. It is our principle method for this type of targeting. It helps us understand on a large scale what the subsurface looks like. What it does is there's two different results that we get out of it. One is called chargeability. What that means is electrical current. IP lines are just a straight line across the ground. And on regular intervals, they put charge into that ground. And what it's doing is it's measuring chargeability and or resistivity, which means doing both. And what chargeability tells us is if there's a sulfide body at depth. The resistivity tells us if there's a silica body at depth. So high resistivity means there's a silica body. High chargeability means that there's a sulfide, a high sulfide content, generally. When you have those two together, that is how Vortex was discovered a long time ago in, I think, 2011-ish. So we're using those same methods. It's a proven way in these kinds of deposits to look for your mineralization. We are doing another type of geophysics called magnetics. Magnetics will help us understand where intrusive bodies are sitting out there. We believe there is more than just one. to the east of Highcroft, and you think that there's a high probability that those are responsible for our brimstone style of mineralization, meaning that there could be other brimstone-type deposits in there. So that's why we're doing IP and magnetics. Again, as all of these tools, they work in concert together. They use one, and it helps you understand the other, right?

Perfect. One thing I'm curious about is what mineralogical differences exist between the oxide mineralization you're seeing at Manganese and that historical oxide resource at Highcroft?

So, quite candidly, historical data from Highcroft, particularly in the oxide, there isn't much data out there, geochemical. big swaths of years that they didn't actually collect silver assays. So I don't really have, I really don't have a way to compare historic oxide mining to what we're seeing now at manganese. They could be related, but we don't really know that.

Great. One thing is, given the extremely high silver grades encountered, and for the folks in the room, they are extremely high, in case you're not familiar with these types of projects, have you identified any unusual mineral associations in the core?

Yeah, absolutely. As we talked before, Argenta tetrahedrite, the nominite, selenostephanite, Those are all unique to Highcroft. They haven't really been identified, I guess, to a lesser degree. But it is what defines that intermediate sulfidation. So that is what's related to those extremely high grade assays that we're seeing.

I appreciate that. One question about how HICRAFT compares. So the structural complexity of HICRAFT, because it's such a large system, how does that compare to other epithermal deposits in Nevada? And what exploration techniques prove most effective in those kind of settings?

So, yeah, I guess structurally speaking, In general, there's not a lot of difference in structural models between one epithermal and another. All epithermal systems have similar characteristics in structure and fluid dynamics. What sets one apart from another is chemistry, really. All deposits are structurally complicated. There isn't one that's just a straightforward, a couple of structures and away you go. They all have structural complication to it. And that complication is different from deposit to deposit. It's different based on um, mythology, you know, how, how your rocks change, uh, from, from one point to another down, down the strata and in your deposit, because that influences how faults break. Uh, it, um, they're, they're different in, in tectonic regimes. They're, you know, regional geologic settings will change structural profiles if you will. Um, All epithermal systems, fluid dynamics are essentially the same. It's hot, mineralized fluid comes up. There's boiling zones, vein textures. All of those things are very, very, very similar from deposit to deposit. What's different about each one is the geochemistry. That's what sets uh these things apart uh from one another um the the the second part of that is what um what sorts of exploration tech techniques it it's proven proven um over and over again geophysics uh in in particular the ip it's geochemistry hyperspectral mapping photography blue inclusion studies you brought up. It's modeling, it's taking all of that data, putting it into a model, learning, understanding, adjusting your drill program, drilling again, learning. This is the scientific method, right? I mean, this is how it's done. You theorize, you test, you adjust and move on, right?

Awesome. That wraps up my questions. I appreciate everybody letting me do my geological curiosity live with you. But I'm going to go to some of the questions live from the chat and some that came in over email right now as well. There's one question from Biotech Moose about 15 minutes ago. He asked if you could tell us more about the gold exploration on the east side of Highcroft. He notes you mentioned it before. Just curious if there's any update.

Yeah. A couple of things that we're doing and I mentioned in the press release is, excuse me, our bay target is one that we're looking at. Again, looking at vein textures and all of that on the surface led to us following up on this target. It's high-grade gold. High-grade is a bit of a relative term. you know, a couple of grams were seen on the surface. And so that's why we backed up and drilled that. So we drilled two holes a day. And again, this is coming back to that scientific methodology that we just talked about. We drilled our first hole and it was tight. There was gold mineralization there. And I think it's key to note that the, Silver to gold ratio is significantly different at Bain, which is way up on the north end of the property. It's way different than what we see at, it's more on the order of two silver ounces to one gold ounce. It's on that sort of scale. So order of magnitude different. This is more indicative of a gold system. This is more indicative of that amalgamatic epithermal type of a system. low sulfidation type system. So we are following up on those gold targets. But back to the drilling, it was tighter than what we had anticipated. So when we go back and we map again, we look, we understand. And that caused us to drill our second hole, which is 6,014. We drilled that further south. So 6,013 is here. We moved that hole back about 1,000 feet farther south and drilled. And then the results we saw in the thing were far more positive. everything we saw there tells us that we're still really high on the system that we need to drill deeper. So that's, that will be that next phase of exploration, um, taking what we've learned, adjusting, drilling deeper and going from there. So there is good gold exploration potential on the property. Um, but, but right, right now, my big focus, um, is still on, on that hybrid silver.

Great. Speaking of, there's one short question that just came in over email, which just on numbers, how much of the deposit is silver versus gold as a whole, what you're aware of so far?

So when we look at the last resource that was published in, I think March of 2023, in that resource, there was 360-ish million silver ounces to about 10.5 million gold ounces from that last report. And we should have a new PEA coming out in the second half of this year. They'll have new results, a new model with it.

There's a number of questions I'm going to all kind of package into one that I think there might be some confusion. So I'll just let you answer it. Is manganese just the name of the target or has there been a significant manganese discovery?

So the name manganese is based on the fact that we see anomalous manganese in that area in particular. That's not to say that we have a mineable resource or anything of manganese. It's anomalous. It's well above background, but it's not anything that's out of this world of mineable manganese resource. I appreciate it.

I just wanted to clear it up since I packaged a lot of questions together, so I thought I'd throw it to you. One question is, and I know this is always a tough question to ask a geologist, but somebody's asking, these are their words, what's Alex's gut feeling about the Highcroft trends? He notes that some Carlin trends can run for several miles. He wants to know if you think the trends are part of a much longer underground trend.

Yeah. I think there is underground potential at Highcroft. That's my gut feeling. What we see at Brimstone, those kinds of grades, those kinds of strike lengths, it's just a matter of piecing together the rest of the puzzle and understanding the offset parts. Not only is there an offset part to the west, there's also an offset part to the east. And we haven't even gotten to that part yet. We need to understand approximately what's east or what's to the west and go from there. But my gut feeling is there is a lot more to this ore body than what we know right now. The kinds of grades that we saw in multiple holes those those are not one-offs those those are indicative of something uh bigger um we know we have to look deeper um um yeah it's it's definitely gonna grow um is it is it an underground uh we're not we're not there yet uh but it's definitely a potential my gut says it's gonna grow

Awesome. Appreciate you sharing gut opinion. Now, I know there's some questions in the chat that we didn't get to today, stuff on cash flow, stuff on order of operations for Highcroft, et cetera. I'm going to send those through to Diane, make sure that the team gets back to you as soon as possible. But I think we've gotten through most of the geo questions. The one that I'll throw to you, Alex, generally, looking at 2024 in retrospect, what most excited you? What did you think was the most exciting element of 2024's exploration program?

I think the biggest thing for me was that learning, that understanding, all of the bits and pieces coming together from brimstone being an intermediate sulfidation system. That is a paradigm shift. It's big. It really changes how we should be looking at a high crop. It really changes uh, the potential, uh, for, for Highcroft. Um, there's a lot of opportunity here and that's, I think is probably the most exciting part of it. Um, and I, and I don't mean to overshadow the other work that we've done in, in Vortex. Vortex has, you know, enormous amount of potential. Its down dip opportunity is big. Um, we learned a lot about Bay. Um, that's, also big both of those programs need a lot of work there we need to understand those complications we have to go through that whole process we only have two holes at bay to really understand vortex where we understand the mineralization is coming from farther to the west that open part to the west is It's complicated. There is no drilling out there to understand that. So it needs a lot of work. And then, again, not to overshadow, but manganese is also really exciting. But it's also one hole, and it needs just tons of work. But summation, brimstone is really exciting.

Well, I will leave it there. Thank you so much, Alex, for sharing. And again, indulging my curiosities throughout today's event. I appreciate it very much. For those in the audience, thank you so much for asking questions. The ones that I didn't get to, obviously it's because they're for Diane and I'll send them directly to the team so they can get back as soon as possible over email. If you have any additional questions, you think of the perfect one right when the webinar ends, which often happens to me personally, please do email them in and I'll make sure they get to either Alex or Diane respectively. But thank you so much for all of your time and Alex for sharing your knowledge with us. Really appreciate it. I feel like I learned something today.

Yep. Excellent. Good talking to you. We'll see you soon.

Have a wonderful day, everyone. Cheers.