Smooth Granite Block

Granite reads dark blue and faintly metallic, and the furniture set built from it leans retro science fiction rather than the ancient temple look you get out of marble. The two clash badly in one room and work well in neighboring ones.

You will leave a granite cave with far more of it than any build needs. Converting the excess into Granite Candelabra is the only bench work worth the time, since the finished lamp is worth more than the blocks and torches that went in. Make the torches yourself instead of buying them and the margin widens further.