The Shard is a place located up in the sky and hidden behind constant cloud cover where fallen angels have been known to meet. It is not used much, and is nearly impossible to find because its location changes, but it is a substitute safe haven for the one the fallen angels lost. It looks like clouds to a human eye, but any other creature inside of it will see the stone inside a glass room in the clouds. If you touch the stone, then you can change the appearance of the building around it.