I found this piece while trail running in Washington state. The beautiful layering within this rock looks like a scenic landscape painting. The light color bands on the outside of the rock caught my eye and I decided to carry it back to my car (a little extra weight always makes a good workout). After cutting and polishing it, I was glad I decided to bring it along. I left one side uncut and unpolished to show the natural beauty of the raw rock.
Rock type: Gneiss, most likely from a basalt
This type of rock is referred to as a gneiss. The banding/layering occurs when a rock experience metamorphic temperatures and pressures and the minerals rearrange into layers as the rock is cooled.
Chemical composition: Gneiss does not have a specific composition, but the layers are typically made up of bands of quartz (SiO2) feldspars and dark minerals such as biotite or hornblende.