‘Rock music’: a new take on the NHM Building Stone Collection |Curator of Petrology

The Natural History Museum Building Stone collection contains over 17,000 specimens and is one of the largest documented collections of its kind in the UK. It is particularly useful for matching stone in historical buildings during conservation work, but not only for that!

Often this collection causes an unconscious burst of inventiveness, and it features amazing pieces of art like this black stone from Derbyshire or this spectacular limestone. This time around it has inspired artist Charles Richard to collect the ‘sonic’ languages extracted from geological materials, a continuation of his master project at the Royal College of Art with a mission to create a series of digital box sets.

Continue reading to learn more about the building stone collection and Charles’ project.

Rock types

There are three main groups of rocks: Igneous, Sedimentary and Metamorphic.

Igneous rocks form through the cooling and solidification of magma or lava.

Sedimentary rocks are formed by solidification (diagenesis or lithification) of sediments. These are formed by the weathering, transportation and deposition of existing rocks.

Metamorphic rocks are formed when existing rocks experience changes in pressure and/or temperature that cause their transformation.

All three types of rocks are used as building stones: Granite (igneous), Travertine (sedimentary) and marble (metamorphic) are some common examples.

Specimen of granite in the NHM collection, igneous rock commonly used as building stone


Specimen of travertine in the NHM collection, sedimentary rock commonly used as building stone
Specimen of marble in the NHM collection, metamorphic rock commonly used as building stone

The Sonic Earth Foundation project

The Sonic Earth Foundation is a project aiming to create an archive collecting the ‘sonic’ languages extracted by geological materials. The mission is to create a series of digital box sets, with each set focusing on a variety of materials in each of the Igneous, metamorphic and sedimentary categories. Charles’s work is introducing a new revolutionary process in how geological sound can be extracted, synthesised and experienced. An example of sound extracted from a rock can be found below.


The recording

Charles explains….

“I record materials with a type of mineral stylus that scores the surface in the same way as a record player scores the vinyl. With a piezoelectric microphone attached to the material, I record.

This initial micro recording is then played back into the material via a vibration speaker; whereby the material is essentially playing itself through its own resonance and subtle surface reading. The result of this second stage means I’ve captured a true audial of a samples inner sound world that’s then cleaned and rendered into digital format.

Samples then become like synthesizers and catalysts of experimental sound worlds but never lose the imprint of their geological origin.”

Charles acquiring the sounds from marbles
The Stylus and piezoelectric microphone
A surface speaker playing back the rock’s sound into itself

This work was conducted in collaboration with Charles Richards at sonic earth, who extracted and synthesized the sounds.

If you would like to see beautiful examples of the building stone collection, please visit the display case on the Hintze Hall balcony, and if you want to see more of these fascinating items do get in touch with the Petrology curator at the Natural History Museum.