Sandstone doesn't have a single, definitive luster. Its luster depends on the minerals it's composed of and their grain size. Here's a breakdown:

* Quartz sandstone: Often has a vitreous luster (glassy) due to the presence of quartz.

* Feldspar sandstone: Can have a dull to pearly luster depending on the type of feldspar present.

* Micas in sandstone: May contribute to a pearly or metallic luster.

* Fine-grained sandstone: Can have a dull or matte luster.

* Coarse-grained sandstone: May have a rougher, uneven luster due to the larger grain size.

So, the luster of sandstone can range from glassy and shiny to dull and matte, depending on its composition and texture.