Former miner Trevor Morris couldn’t get enough of going underground. In his spare time he went caving and discovered the beauty of phosphorescence.
IT WAS a chance encounter with a 'frozen waterfall' in a South Wales cave many years ago that got Trevor Morris interested in phosphorescence.
A miner by trade, you'd have thought he'd have had enough of going underground during his working hours. But no, he was also a member of a South Wales caving club.
"Mining and caves are different," says the 72-year-old, who moved to Yorkshire to work on the Selby coalfield a quarter of a century ago, recalling those long-off days from his terraced house off Bishopthorpe Road. "You've got a support every four feet in a mine. In a cave, you've got this big void."
It was on a caving expedition that he happened to lean against a flow stone, one of those extraordinary cave formations that look like a frozen waterfall. "When I moved away, there was a slight glow left behind."
It was phosphorescence – a process in which energy such as heat or light absorbed by a mineral is released again as light, so the mineral glows.
Trevor was intrigued. He devised a camera that allowed him to photograph these 'glowing' minerals, and used it to take photographs on his caving expeditions. "There's a saying that in caves, you should take nothing but photographs, and leave nothing but footprints," he says.
Then his interest switched to fossils and particularly to ammonites: sea dwelling creatures related to modern-day squids, which had distinctive spiral shells and were found all over the world between 240 and 65 million years ago but died out at the same time as the dinosaurs.
Trevor discovered that by shining light on the fossils, then switching the light off, if he was quick he could photograph the phosphorescent glow they gave off.
The result is a series of stunning images of ammonites – with no digital trickery involved at all, he stresses – which reveal the structure of the fossils in a way you can't see in natural light. You can see, glowing bright red or orange, the individual chambers that showed how the ammonite grew; and even, appearing as a black line, the hollow tube running around the outside of the spiral that he was told by a palaeontologist was used by the creature to maintain buoyancy in the water.
The phosphorescence emitted by a mineral changes from one end of the light spectrum to another over a few milliseconds. So if you photograph the same fossil as its phosphorescence changes, you get different parts of the structure highlighted.
Trevor – whose wife, the York benefits advice worker and anti-poverty campaigner Pauline Sweeney, died six years ago following a long illness – keeps his exact method a secret. And it doesn't, anyway, work on Yorkshire ammonites, he says. Ammonites from Madagascar seem to work best. "There must be more exotic trace elements in Madagascar."
So he buys his ammonites, and has now built up a good collection. It is only in his photographs that their true beauty shows, however: creatures that died millions of years ago brought to glowing life by the mystery of phosphorescence and the magic of Trevor's camera.