Goethite!

This rock appears to be limonite or goethite, both iron oxides. Here's why and how to distinguish them:
Reasons for the Identification:
* Color: The rock exhibits a range of brown, yellowish-brown, and reddish-brown hues, which are typical for iron oxides.
* Texture: It has a porous, botryoidal (grape-like clusters) or earthy texture, also common in limonite and goethite.
* Appearance: The overall appearance suggests a hydrated iron oxide mineral.
Distinguishing Between Limonite and Goethite:
* Limonite: Limonite is not a true mineral but rather a mixture of hydrated iron oxides, primarily goethite. It's often amorphous and can appear as a rusty coating or in various forms like stalactitic or botryoidal.
* Goethite: Goethite is a specific iron oxide mineral (α-FeOOH). It can have a variety of colors (yellow, brown, reddish-brown) and forms (fibrous, botryoidal, massive).