[Vol.6] Ch.6 Fluorite Deposit
During the remaining two months of winter, we checked about as many spots for sulfur as I had in the first month. Each spot got further and further from the road, which led to slower progress. Ultimately, we found a second potential source of sulfur. The new one is even more remote than the first, though it does appear to only be 20 feet underground. We decided that while the first potential source is having a scouting tunnel dug into it, the forest management teams will start searching for a safe path to this second source, so we can repeat the process there as well.
All these potential areas that we've checked have either been on the side of the island with the road going around it, or close to the ore roasting area, meaning we have about a quarter of the island that we have basically left untouched due to the difficulty travelling through the craggy terrain there. It's probably worth considering expanding our surface road infrastructure around that side of the island, if only to aid in potential future projects.
I talked it over with Zeb, and he had a pretty good idea. Currently, in fall and winter, we're having some goblins manually breaking rocks in the reservoir to expand it and potentially gain stone shaping when they prestige. Accompanying them are a handful of dwarves and goblins who clean up the jagged rockfaces behind where the manual breaking is happening. This spring, that group is doing the digging into the potential sulfur deposits. During this upcoming summer, the reservoir will be in use for hydroelectric power to separate hematite. Zeb had planned to have them expand out some of the terrace farms during this time, but he was indifferent to having them build out some roads instead.
After additional discussion, this also means we'll have to halt jetty construction during those months, meaning we'll have even more teams available for road construction. Building a road uses much less stone than building a jetty, but without a large supply of stone, building the jetties would quickly consume all our stockpile. So, during summer, we'll have multiple teams building out roads. In fact, we have too many teams for working on a single road, so we also picked the heaviest travelled dirt path used for getting to some of the terrace farms, and we'll be turning that into a proper stone road. Being able to bring carts along that road should make harvest season much easier for the farmers who work there.
Fifteen days into spring, the first potential sulfur deposit was breached, however, there wasn't any sulfur present. What we found instead might be more valuable though. Reddish orange crystals that appear to be fluorite. By the time the tunnel had been opened to the atmosphere, and I was informed of the find and came to look, the tunnel had become unbearably hot. Even I couldn't even get halfway down the tunnel, and I have heat resistance. I was concerned about the crystals potentially melting themselves, so we re-sealed off the tunnel with almost ten feet of stone.
Unfortunately, to use this fluorite, a lot of work will need to be done to access the deposit safely. I can't quite get close enough to determine the absolute size of the deposit with tectonic sense, but I could at least determine that it's large enough to be worth exploiting. Even then, just because some of the fluorite seems to be the heat producing variety doesn't mean all of it is. For the next month, I'm having all the miners who were close to the deposit report in for daily checkups, and once a month after that, just to keep an eye on their health.
In order to access the deposit safely, I'll likely need to dig in from an area a decent distance away, so that mana in the air doesn't seep in too quickly. Even then, I suspect the crystals will get very hot due to the sheer volume of them. Generally speaking, individual crystals seem to be able to dissipate their heat into the air quite easily. The issue is likely the volume of the deposit, alongside the thermal conductivity of the surrounding rock. The heat that the crystals produce just doesn't have anywhere to go easily, and so it just builds up over time.
One potential option, if I wanted to get a handful of crystals at a time, would be to reopen the mine every so often, and then cut as many crystals as we can out before it gets too hot, then seal the mine off again and wait for it to cool down. That might at least work until a longer tunnel is dug. One issue with that, however, is oxygen deprivation. If we leave the tunnel open to get oxygen in, it'll heat up, driving the air inside out of the tunnel, and the only way to cool it is to close it off, pulling a vacuum inside. When we open the tunnel up, the air outside will rush in, likely bringing a bunch of mana with it. Meaning the window to actually harvest crystals before everything heats up will be very small.
Regardless, I want to wait until the end of the month to make sure that none of the miners get sick before we open it back up. I will, however, start excavating a new tunnel myself while I wait. I plan on digging to the side, and then tunneling around the deposit, and entering it from the back, with the hope that the extra distance will be enough to make the heat bearable inside. It'll take much longer than a month for me to mine that far myself, so I won't need to worry about an accidental exposure to potential toxins in that time.
Thankfully, in the month of monitoring, none of the goblins got sick. Well, outside of the first day where a few showed minor symptoms of heat stroke when they left the mine shaft after it heated too much for them to stay inside. The second potential deposit did produce sulfur, so we're back in business for sulfur harvesting. I am worried about us running out of elemental sulfur at some point, so I've started to think about how I'd go about recovering sulfur from the sulfur dioxide given off from roasting our ores.
We're likely losing literal tons of the stuff to the atmosphere, which I'd prefer to recover if possible. Unfortunately, things like this are never free, and I'd want to find a renewable resource we could trade to produce the sulfur. If we end up trading something else that is limited in exchange for the sulfur in a reaction, it's just not worth it. If fluorite research yields good results, then I could potentially use hydrogen as a reactant to produce solid sulfur and water vapor.
We could do that currently with electrolysis as well, but that would require significant energy consumption from the hydroelectric facility, which would mean we wouldn't be able to separate as much hematite. If the fluorite research doesn't yield any results by the time we've run out of hematite to refine, then I'll consider it to be a viable option for recovery.
I'm only about the third of the way done with the tunnel that I'm digging to the fluorite deposit. Given that no one got sick, and we don't need everyone extracting sulfur at this point, I'm planning on bringing those miners back here to help me dig this out, so it can get finished quickly. With the extra labor, I might even extend the tunnel further before turning back, just to be on the safe side.
With the extra labor, we completed the new tunnel in just under twenty days. It would have been less, but I decided to extend it further. The tunnel current digs into the mountain for 200 feet, then turns, goes another fifty, before returning and running into the deposit after another 110 feet. The temperature is still a bit too hot for other miners, but with my heat resistance, I can handle it, meaning I can extract fluorite. So, that's exactly what I started doing.
Due to the potential danger of bringing too much of it up at once, and also exposing more of it to air, I dug multiple small rooms near the deposit, which I sealed off with doors. As I break the surrounding rock to recover crystals, I'm being careful not to let too much of it pile up. I take the time to sort it as I go, and store the partial product in the rooms with the doors closed to limit their exposure to mana. That said, as I've mined into the deposit, it's gotten a little hotter due to the increased surface area as I've dug into it.
To help with this issue, I've started to cover the floor, walls, and ceiling of my mining tunnel with stone, which seems to have helped a little. Most of the crystals I've recovered are quite small, but I've recovered three that are comparable in size to the ones that the merchant gave me.
I took a few days to test how much of what size crystals I could reasonably store in a box to transport from the surface to the lab basement. As previous experiments indicated, the smaller the crystals, the larger the total volume I could safely transport as their efficacy goes down with their size.
After another twenty days, I called it for now. I got those three larger crystals and about two hundred pounds of smaller sized crystals that I can experiment with.