A few covers I have collected on labels starting with H to L. The first one is on Hi-Infidelity. This company put out joke record jackets with no records in them. If you want to see more of them, go to: https://musiceureka.wordpress.com/2014/10/28/hi-infidelity-records-complete-series/
The other really interesting one here is the Calvin Jackson jazz record on Liberty. The material is velvet. There have been other velvet covers, and aluminum foil, and probably other strange materials.