Material variants for bookshelfs.

If we already have wooden shelf variants, why can’t we have book shelf and chiseled book shelf variants. Even cooler would be to have other matrails to make bookshelfs too, such as quartz stone, and maybe brick. I would really like this because if I want to make a library I always have to use brown or oak to set the tone. Otherwise it falsely stands out. Very simple and a logical addition.