Sedimentary Staff!

This rock has a smooth, unpolished surface with a mix of earthy tones like brown, beige, and some greenish hues. Based on its appearance, it could be a type of sedimentary rock or a metamorphic rock. Here are a few possibilities:

Sandstone: Sandstone often has a grainy texture and can come in various colors depending on the minerals present. The brown and beige tones with some greenish patches could suggest iron oxides or other mineral inclusions.
Quartzite: If the rock has undergone metamorphism from sandstone, it could be quartzite. Quartzite retains some of the original sandstone characteristics but is usually harder and more compact.
Conglomerate: This type of sedimentary rock is made up of rounded pebbles or larger fragments cemented together. The rock in the image might have some larger grains or pebbles embedded, suggesting conglomerate.
Serpentinite: If there's a greenish tint, it might indicate the presence of serpentine minerals, which are common in serpentinite, a metamorphic rock formed from the alteration of ultramafic rocks.