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There is a group of people with about renaissance-level technology clearing out underground granite. They have no access to work animals. 700 men are working at any given time.

Mining
Using renaissance era black powder blasting, at what rate could the granite be removed from the wall?

Transportation
Given a human drawn wood-wheeled cart being pulled 100 meters across a granite floor, how much granite could be moved at one time by 2, 4, or 6 men?

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This question asks for hard science. All answers to this question should be backed up by equations, empirical evidence, scientific papers, other citations, etc. Answers that do not satisfy this requirement might be removed. See the tag description for more information.

  • $\begingroup$ What does "clearing out underground granite" mean? Are they mining for granite? (Don't think so, granite is usually exploited in open quarries.) Are they mining for something else? $\endgroup$ – AlexP Feb 18 '18 at 19:24
  • $\begingroup$ Black powder was first used for mining in 1627 according to the internet. So, a Renaissance-era black powder blasting would proceed at the rate of zero, since this method wasn't in use during the Renaissance (which is commonly accepted to have ended in 1600). $\endgroup$ – kingledion Feb 19 '18 at 1:38
  • $\begingroup$ First thing first. They would not use black powder. Explosion mining of granite leads to mini cracking of stone. Second, there is a reason why granite was obtained in quarry and not mine. Third - all other question can be answered by looking at historical records of quarries or builder (how many granite hey ordered from whom and what time it took to delivery) $\endgroup$ – SZCZERZO KŁY Feb 19 '18 at 14:40
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Instead of blackpowder, renaissance masons inserted wooden pegs into natural cracks, soaked them in water and when the wood swelled, their stone was broken free.

Unfortunately i've yet to find labor numbers for manual quarrying in the correct period, but these figures from estimates of the construction of the pyramids are probably not far off from the manpower needed in the renaissance.

"In the open quarries of Aswan the granite was worked as follows (more information): The stone was pried from the bedrock by inserting several wedges. First a series of holes has to be drilled. We propose, that like in the ancient quarries of Europe not an actual drill was used but a forged chisel. With the hard granite this is only possible with iron tools. The stone has to be cut along its cleavage plane, that is the structure by which certain rocks split most readily. A man sits on the stone holding the chisel perpendicular to the surface to where a hole is placed and three men pound on the chisel with sledge hammers by turns. After each hit the chisel is rotated by one eighth until the hole is 10 to 15cm deep. A row of holes is drilled in such a way along the cleavage. Now a pair of metal shims are inserted in each hole with a wedge between and lubricated. Each wedge in the row is pounded until a thin crack forms between the wedges and the rock can be levered apart. For the granite stones we need 2 teams in two shifts with one man holding the chisel and 9 men (3 times 3 men) pounding. Each half hour the shift is relieved, because this kind of work is very exhausting. An average granite stone can be cut in such a way in one day. Even calculating that it takes 20 times longer to cut a granite stone (1 block every 20 days) it was still possible to cut the required blocks in only 10 years. A team of 20 men is loading the granite blocks onto sledges and 25 men haul them to the harbor (1.5km away - we calculate 120 min. to haul a stone there and walk back). A team can haul 4 stones per day (with rope rolls). Still tied to their sledges the stones are shipped down the Nile to Giza. If one of the large 40-tons block had to be transported, additional workers from other quarries were asked to help." so we can assume most of the stones were not 40 tons (40 ton block = roughly 15 cubic meters)

from https://www.cheops-pyramide.ch/khufu-pyramid/pyramid-workers.html

http://graphics.stanford.edu/projects/mich/pietrasanta-20nov98/pietrasanta-20nov98.html (probably anecdotal history from the quarry they were visiting)

https://en.wikipedia.org/wiki/Stonemasonry#/media/File:Marmor-spalten.jpg

https://www.aqua-calc.com/calculate/volume-to-weight

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  • $\begingroup$ although now that ive answered it, i wonder if it shouldnt be in the history stack $\endgroup$ – Patrick Zissou Feb 19 '18 at 11:48

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