Lunar Boom Town/The Ruby Palace

The Ruby Palace would be an exceptionary luxury hotel whose outside walls were composed of synthetic ruby.

Ruby consists of highly pure aluminium oxyde doted with chromium. While chromium is rare, it is needed only in very small quantity. The other elements, aluminium and oxygen are abundant on the moon. In the absence of an atmosphere and with cheap energy from solar energy it is much easier to purify the raw material and fuse new layers on the existing building than it would be on earth (there is no atmosphere to carry off the heat).

As an enhancement, very thin layers of piezoelectic materials coupled with light emitting diodes could be interleaved to damp vibration which would otherwise propagate and possibly be harmful in the absence of the damping of an atmosphere. The energy would transform not to sound as on earth but to sparks of light.