The sisters, who grew up nearby in the Hawkesbury region, have brought together their backgrounds in glass (Caitlin) and music and sound (Natasha) to create an installation that encourages visitors to explore and play as they take in the exhibition, Tephra. 

The project was sparked after Natasha did an artist’s residency in Mt Wilson two years ago and became fascinated by the geology of the area. “The basalt caps and temperate rainforest gave me some amazing soil and wind recordings while I was on residency. The whole experience led to conversations with Caitlin about the volcanic history of the area and tied in nicely with Caitlin’s own research on the minerology of glass. We continued to return to the area and over time worked together to create the installation,” she explains. 

They called their collaboration Tephra, the word for the fragments of materials produced and flung out by a volcanic eruption. A nod to both the geology of the area and the way in which they chose materials and sounds in the landscape and played with them creatively to create their installation.

The sisters’ process involved exploring the landscape, taking texture impressions, and recording sounds (some inaudible to the human ear). These impressions were then layered and reworked to create moulds for their sculptures of glass, bronze and concrete. 

Tephra is a multisensory installation on display at the Penrith Regional Gallery. Courtesy the artists.

“Our work is guided by material experimentation. Processes of fragmenting, sampling, and layering are reflected in each part of our studio practice spanning fused glass, concrete, electroformed bronze, and sound,” says Caitlin.

The resulting immersive exhibition engages audiences in a playful multisensory experience, where you can feel, hear and even touch the sound.

“Visitors are encouraged to touch and listen to the sculptures as sound emanates through bronze, glass, and concrete,” says Natasha. “Hear how each material colours the sound according to its resonant tendencies. Bronze cymbals give a warm glow, glass favours high-frequency overtones, and the concrete conducts low frequency sounds through your bones.

“It is an uncanny experience when you’re listening to sounds that cannot be heard by the human ear alone. The recordings are taken using specialised microphones which allow us to hear sounds from deep beneath the Earth’s surface, underwater and through trees. It is a listening environment quite unlike any other.”

“We’ve turned the material – bronze, glass and concrete – itself into a speaker,” says Caitlin. “It’s a process of mediation, from the recording then amplifying through the materials in the gallery.

In some ways, says Caitlin, “we are sharing the feeling of going on a bushwalk where you become attuned to different sounds and sights. We wanted to create a playful sense of movement and discovery in a place.”

Tephra is most definitely not a look and don’t touch exhibition.

“Something we’ve noticed, in these first days of the exhibition is how quickly kids who visit engage with the work,” says Caitlin. “They’re so keen to touch everything and listen, and they quickly catch on to what is happening with the sounds. It’s great to see the way in which the exhibition sparks a sense of wonder and play. It’s what we were hoping for.”

Tephra, curated by Nina Stromqvist, is a free exhibition and will be on display at the Penrith Regional Gallery until April 28 2024.