| Where | Great Broughton Village Hall | Type of Event | Illustrated Talk |
| When | Monday 17th February 2025 | Tutor | Chris Twigg |
The lecture was delivered by Chris Twigg, who is an archaeologist and caver. He was also for several years, “Our Industrial Heartland” Officer for Redcar and Cleveland Borough Council. We had a good sized audience. Chris’s presentation was lively and well organised. This was a well-researched and mastered subject.
Chris began with the general point that North Yorkshire had both jet mining and ironstone mining industries. The peak of the ironstone mining covered the time from 1848 to 1964. Jurassic ironstone was the metal ore and the industry was carried on in a way very different from jet mining. Ironstone mining was highly organised whereas jet mining was small scale and required simple equipment. Ironstone lies in seams and the miners follow the seams. With jet it is more random. It was more a matter of fortune if the jet was found. The usual technique was to dig into the hillside to create a gallery and then to retreat towards the entrance pulling the roof down behind you. A search would be made amongst the debris to find the jet. Chris found many cross passages in the mines so that they form long networks rather than being isolated single drift mines as previously thought.
Asking the question “What is jet” we were informed that it was fossilized wood obtained from many different kinds of conifers. The idea that it is solely from the monkey puzzle tree was dismissed as myth. And there were different kinds. “Cored jet”-it has a core of iron and is useless. “Midway jet” which is brittle and could split easily. The preferred type is “Plank jet”, because it is pure in the middle.
The history of jet working has a range from about 4000 BCE until the modern day when it was established at Whitby in 1808. It gained some prominence at the Great Exhibition and became popular as jewellery associated with mourning. Whitby jet is mainly found in a two mile stretch of coast from Robin Hood’s Bay to Boulby, but most of the finest jet is produced inland. Mining was operating in Great Broughton in 1873 and along the scarp of the hills at other sites. In particular, Chris wished to emphasise the inland jet mining industry in North Yorkshire.
Chris’s talk was well illustrated. There were many photographs of old abandoned workings underground. There were maps and surveys of the workings and that research continues. We were warned that old mines are dangerous and it was advisable to keep well away and keep out. The material was absorbing and the audience was attentive. Questions were asked. Samples were passed around the audience which added to the interest. Clearly, the audience appreciated the visual and the tactile. Members of the audience were invited to take a small sample/fragment of jet. The time passed easily and the audience was informed and entertained. An enjoyable evening