The play of light and shadow is a recurring theme in Ann-Margreth Bohl’s sculptures.

Lumen (the name comes from the standard unit for measuring light) was inspired by two recent journeys. The first was to Portland in Dorset, where Ann-Margreth first began stone-carving (‘I feel a very strong connection to the place’). Looking at cut blocks that were left in the old Portland stone quarries, Ann-Margreth became interested in the spaces between them: ‘I watched how the light moves round in them, at different times of day. A void can be a space where a lot of things are happening.’

The second journey was to Iceland, where Ann-Margreth was fascinated by the abandoned shell of an airliner, which had been left sitting on the black sand of a volcano after it was forced to crash-land, in the Seventies (no-one died). Light coming through the square windows into the dark and empty fuselage again changes the spaces in between.

Lumen plays with some of these ideas. It features four limestone blocks cut into a series of angular planes. There are subtle variations in the angles in the white stone, each of which is like the angle of sunlight at a given moment, as if it were making solid something that is usually fleeting. ‘It’s like I’ve frozen the movement of the light,’ says Ann-Margreth. ‘As humans we can’t do anything to stop time, but we often try.’

The white blocks rest on a bed of black sand: an echo of the Icelandic volcano. For all their precision, the blocks are carved by hand, using Ann-Margreth’s own distinctive method of measuring and calculating angles.

For Ann-Margreth, there’s a pleasing paradox here: ‘working in an immortal material, but using it to represent something as ephemeral as the movement of light’. There’s also something of the Zen garden about the installation: ‘you need to spend a bit of time with it.’ Ann-Margreth has recently been working on a much bigger scale, with her three-metre-tall sculpture Passing Light, for the National Memorial Arboretum. Lumen, too, could serve as a model for something much larger.

Written by Matt Shinn