Number 6 is very familiar. Lots of them here.Been trying to photograph chimneys against a blue sky for yonks. Will switch to your method.
Here's the story about the last (bottom) chimney:The bricks were recycled (in 1911-14) from the original Union Lumber Company powerhouse. That's why the bricks are white, pink and black. The black bricks were cristalized by the heat from the 24/7 powerhouse.By the way, the fireplace seems gigantic inside the living room of this Crastman style home.
Thanks a lot for the information of what this chimney is made from. I think I will add it to my Fort Bragg Oddities brochure the next time it is re-printed.