[...] Also, all blocks must be of the same colour.
/returns to thread having just deconstructed about 150 units of temporary dacite block walls and filled these gaps back in with recently produced sandstone blocks to match the rest of the ground-level walls[1]...
You mean they don't have to be?
Next thing you'll tell me is that you don't need to stick to just one colour of Lego bricks when making a house/gun/airplane/spaceship/closest-approximation-of-a-[cube/sphere/torus]-one-can-get! For that matter, I'm willing to hazard a guess that you're not even going to commit to just
one type of brick, mixing standard 2x4s and 2x8 flats and the like!! By the scornful way you suggesting uniformity, I can tell that you're pure-blood anarchist and we're not safe in our (standardised) beds!!!
I'm going to have to watch out, or I could end up with my workplace fortress (currently walling up with cyan-coloured ice, whenever I have a moment or three to spend on it) could end being patched in with microcline!!!! And that'll lead to further patching in spoilermetal!!!!!
[1] I might make the first-floor level all marble blocks, but will probably continue with the sandstone blocks. Let's see, I need (80*4)*4 blocks for the perimeters alone (whether walls or fortifications), plus I'll have to lay down some floors ((79*2*6*2)-(36*4))*4), stairwells (6*6)*4*(1up/down + 1down), ramps and abutting walls to leading up from the ground floor (?6*6*2)*4)... So, let's call it a nice round 9,000 blocks needed... I may not have enough non-aquifer-ridden sandstone deposits. Maybe I should see how far the marble layers spread and swap the current entirely-sandstone ground floor perimeters for ones entirely of marble, and then build up...