NOVEL NEXT [Vol.5] Ch.46 The Mining Tunnel Part 2
After only a few days of helping the mining team, I improved their efficiency significantly, making me wish I'd spent a longer amount of time working with them previously. The tunnel only has one track, so the mining team was hauling one cart out at a time, which was resulting in a much slower extraction rate than what they were capable of. How I improved it was fairly simple. I figured out how long it took for one miner with stone shape to run out of mana, and then used that time to figure out how long it takes to load a cart, and how far it can be pushed in that time. After that, it's just a matter of having a number of carts in the cave that meet at different lengths, where they move the load in one cart to the next one. It's not as efficient as having two cart lanes, but it's much faster than before.
All in all, I helped them mine for 22 days before I decided to investigate the interest point underground. With more tectonic sense points to judge from, I got the general sense that one of the things I detected was the edge of a dome shaped intrusion in the layer change underground. The edge that I detected seemed to be about 80 feet wide, though based on the curvature, I'd estimate it's generally dome shaped and about twice that width. We're almost a mile into the mountain now, and probably around 1000 feet under the surface.
The plan now is to make a loading and unloading point attached to the tunnel over the deposit, and then dig down towards it. While the mining team works on that, I'm going to check in with Zeb and see how things are going with his teams. Given that the last ore deposit like this took a couple of years to extract fully, I'd like to have one of the construction teams get the tunnel expanded to the full width to that point, to improve the extraction speed. Though I suspect I'll have to wait for the team that's building the second sea wall to finish their work before I can borrow anyone.
As I suspected, it seems like I won't be able to borrow any construction teams until next year. According to Zeb, they're getting quite a few new stone shaping goblins thanks to making the terraces along the hillside. He wants the new ones to spend at least half of a year on an existing team before they're put on a newer one though, which is why I'll have to wait. They're gaining quite a few levels though, since they're having to clear cut the hillside as they do their work, which is why we're getting so many stone shaping goblins so quickly.
The terraces are actually quite intricate, which is why we needed a build team dedicated to making them. After the dirt is hauled off the stone, regular goblins break the stone into an approximately level surface, then stone shaping goblins cut channels into the layer, to facilitate water drainage down to the next layer. Above that, fine gravel is layered back on, and then finally the dirt is put back on top. Anything larger than gravel is then hauled off to the other side of the island. With the sheer number of workers, Karsh has been quite busy repairing and making pickaxes.
They're making great progress though. They're adding about six acres of farmable land a month. Ultimately, that means we're adding about 15 demons worth of food a month in available farmland. Given the majority of our island does require terracing to farm effectively, it actually is quite useful, even if it doesn't sound like that much. It also helps prevent mudslides, which do happen occasionally here.
So, depending on the time of day, I guess I'll either help the mining team, or work on expanding the tunnel further. During the day, I can hire some regular goblins to help me haul stone I cut from the tunnel, and at night, I can pile up stone in the loading area deep in the mine while everyone else sleeps.
It took us 44 days before we finally made contact with the suspected deposit. It took a while because we needed to dig a horizontal shaft first, so that we were centered over the deposit itself before digging down. Though once we started digging down, it only took a few feet before we started seeing different materials. Tectonic sense also helped me to locate the actual trunk of the deposit, which was a little off center from the dome, with a slight angle.
First, we dug partially into that different layer of stone, the layers we've been going through have been a very dark color, while this new layer is lighter in color, with more pockets, and also weighs quite a bit less than the previous layers. The dome material was a dark red color, bordering on black, and was significantly denser. I hadn't expected it to be an ore, given the last top was gypsum, but given how different this was, I figured it would be worth a test.
It took a lot of heat to get it to break down, and there was a significant amount of slag and impurities, but it seems to have made iron, which, given it's reddish color, I suspect it's hematite, though it's littered with impurities. If it is hematite, then it'd be worth setting up the power facility using the dam, because the easiest way to purify it should actually be to crush it and pick it up with a magnet, leaving all the other rock behind.
Since we hadn't planned to extract the whole dome, we actually weren't set up properly to harvest it. It'll take me some time to make a hydroelectric plant though, so I told the mining team that we'll eventually come back to extract it, but for now, they should keep digging down.
After 21 more days, we'd made it through a few different kinds of materials. We found more quartz bearing rock, galena, sphalerite, and pyrite, though they're fairly intermixed this time, which makes it much harder to extract them. Unlike the other deposit, where the crystal materials were larger, and layered more distinctly, here I can find sphalerite and galena and pyrite in the same chunk of rock. Thankfully, removing the zinc and lead from the pyrite should be fairly straight forward, so other than needing a few more personnel working on it, it shouldn't cause many issues.
A new use of tectonic sense also gave me a better idea of the deposit's size. If I had to guess, it's probably between five and ten times the volume of the last deposit, which would mean that the mining team will be working for decades before they extract everything. In practice though, within a few years I would like to have many more people working on mining, so it will probably last us significantly less time than that.
I also realized we needed a better system than manual handing off of stone materials to different carts, so we've started installing passing zones periodically in the tunnel. Since everyone has a torch of some kind, it's easy to see when someone is approaching, and carts loaded with stone have the right of way. This way carts leaving the mine easily make it out quickly, and empty carts can go to the loading area where someone is filling them for the return trip.
I ultimately decided that we should have a couple goblins doing manual sorting of the ores brought out first, to try to classify them based on where they should go first for treatment. If the rock was majority galena, with it's silvery black hue, then it should obviously go to lead melting first, to remove most of the lead. The tailings from that can then be sorted for sphalerite or iron oxide content if necessary.
If the ore is more sphalerite, but still has a lot of lead, it has to go through a new lead furnace that also has a zinc collection chamber, which took me fourteen days to put together. Lastly, if the sphalerite content is low in a pyrite sample, then it go through a lead furnace first to melt off the lead, then be treated like normal pyrite.
Ultimately, we could use pretty much all of our existing furnaces and roasting ovens to utilize our new deposit, but they do need extra maintenance due to the amount of cross contamination. I brought on a total of 12 new goblins to handle sorting and assisting with maintenance as a result.
Due to the extra sorting and maintenance though, ores are processed a bit slower before giving us useful metals, which itself could be considered a problem, but the shape of the deposit and its contents actually make that fine. Because the second layer is largely quartz laden rock, I've instructed the mining team to spend some of their time mining that layer out over digging deeper into the central root of the deposit. The quartz layer, from what I can tell with tectonic sense, is like a secondary domed layer, meaning there should be a sizeable amount of it.
The whole deposit looks a bit like a melting ice cream cone, with two different partially melted scoops, and a central cone of ore underneath, but that central cone is considerably smaller than the partially melted ice cream on top. I think that spending all this time doing hard labor with days without sunlight has given me weird cravings for food that everyone else doesn't even know exists, or at least, that's what I'm blaming it on.
Anyway, to get to the secondary layer, the best way forward is to also mine out the top layer, meaning we'll start collecting a lot of hematite. Which also means I need to see if we have enough available warehouse space, or if I need to make room elsewhere.