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