Gold's got a fairly low melting point and efficiency isn't too much of a concern, so we might be able to smelt the stuff over a campfire and then store nuggets or ingots rather than dust, cutting out whole lines about baskets. Send Mari a storage seal full of gold, she probably won't need to be told exactly how to make OPSEC-appropriate use of it.
Nah, campfire heats at 300C and gold melts at like 1000C, maybe you're thinking of lead? Lead melts at campfire temps.
Why I Think the QMs Should Let Us Mine 10+ Metric Tons of Gold From This Mine
@eaglejarl @Velorien @Paperclipped
Historically, gold was most often mined from
alluvial deposits through something called
placer mining.
This is basically just a fancy way to say that gold was most often mined from stream beds by panning. That is, using flowing water to separate stuff based on its density. Since gold is much denser than sand or silt, it's easy to separate this way.
That gold is deposited in the stream bed by the process of
weathering. Gold exists in nature most commonly as a pure metal or solid solution (alloy) and not an oxide. So when gold-containing rocks are broken down by water and wind, the gold dust inside runs off into rivers and makes its way downstream.
When the fast-moving river slows down, due to bank widening or something similar, the gold dust will drop out of suspension and sink to the bottom of the river. Where it builds up over millennia.
Now that the basics have been covered. We can talk rough estimates of how much gold there is in this mine.
The alluvial layer is usually between 0.4-4.0 m deep, with 0.7-2.7 m being common. I'm going to round this off to 2m thick on average.
Hazou can make a 64mx64m×64m cube with a cast of ES at Effect:5
So assuming the alluvial layer averages out to 2m depth across the AoE, that gives 8192 cubic meters of ore, per cast.
Now if we can find the concentration of gold per metric ton of ore, and the density of the ore, we can calculate the gold content per cast of ES.
Gold content ranges wildly between different ore bodies. So it's tough to make assumptions here. A
quick Google search says that "high-grade" ore is 20-100g gold/ton (ppm) and "low grade" is 1-4 ppm HOWEVER and this is a
huge caveat. That's for modern commercial gold miners, who mine on an enormous scale compared to Iron Age farmers. So they can utilize much much less concentrated ore bodies. I suspect that an Iron Age mine would be "mined out" when the concentration of gold dropped much below 10 ppm. I am going to
estimate the concentration of this mine at 10 ppm. The QMs may determine our collective fate by adjusting said concentration. Although I feel like lower than 5 ppm is somewhat unreasonable.
Now for the density calculation. I found this number of
3.3 metric tons/cubic meter for the density of placer ores.
Now putting it together.
8192 m^3 ore * 3.3 metric tons/m^3 * 10 g gold/metric ton = ~270kg gold/cast of ES.
Now to estimate the size of the mine.
This website says that "The width of placer gold deposits is generally 50-300m, and the length can reach several kilometers or even dozens of kilometers"
To simplify the math. I will say that this placer gold deposit in question is 128 m wide (2 ES casts) by 3200 m long (50 ES casts)
For a total of 100 ES casts. Which is 270 kg * 100 casts = 27 metric tons of gold.
Now let's do a quick check back with some real mines to see if this number is reasonable. 27 metric tons of gold is about 1,000,000 oz (a little less) comparing to real mines in the Yukon and California, it seems like
total gold amounts mined were often in excess of 2-10 million oz. So 1 million oz for the total content of a partially worked out, relatively small, mine seems reasonable to me.
Okay, so how many ryo is this? Well at current prices, it's about $2300 per oz of gold or $75000 per kg. That would be about $2 billion for 27 metric tons.
However, it's worse than that, historically gold has been worth more that that per oz. Inflation adjusted prices are about $3000 per oz in medieval Europe. That would put us at ~$2.6 billion.
Conservatively, it's 20 billion ryo at the 10-to-1 dollar-to-ryo conversion factor that we've used in the past.
Assuming there's a mint fee, but that gold does a little better than $2,300 per oz in PPP, we can probably expect to get roughly 20 billion ryo out of this.
