can someone help me comstruct this material? ( stone buildings)

i’m curently in making a building that is a old style stone building which has a green copper roof on it, but i’m stuck on both the green (rusted copper) material and the stone material, i’m kinda fuzz on how would the stone look like cuz i’ve never seen a building like that before.
it kinda like a old planetarium (which has a rusted green copper roof and rock made, i have thought of marble but it doesn’t look right, perhaps limestone?). i would like some help one those material.
the lime stone should be in brick form, or at least i think so, cuz the building is 2 floors high, if not, just a whole block carved out?
here’s some pics of roofs

oh, and talking about bricks, is there a way to discontinue the patterns of the bricks other than just mix it with 2 materials with the factor of brick material

Your question is vague, what exactly do you need help with? Copying the look of the copper?

There are two ways to create the block patterns here.

1). Model it, the bevel tool should be of great help in creating the seams once you lay out the pattern with edges.
2). Use a texture, in this case, making one should be as easy as drawing lines in a paint program.

After you do that, you would use a diffuse material with a high roughness value for both the limestone and copper as well as a glossy component that also has a high roughness value (which would be more visible for the copper).

The more complex detailing however made need to be modeled by hand and repeating across the building using either the array modifier or by duplicating the pieces yourself (unifying them with the ‘remove doubles’ operator and then connected to the rest of the mesh using Ngons), I hope this helps you get started.