NEHL - An unnamed colliery is featured on the 1866 Ordnance Survey map along with a shaft directly next to the main lane north east from Eshott. It appears to have been a small facility with one main building in use. The colliery had disappeared by the 1890s, though the shaft was still extant.

(20/12/24) - There are two separate workings at Eshott shown on the First Edition Ordnance Survey, with a coal shaft identified on the main land and another colliery against the route of the Eshott Burn. It doesn't appear related, but documents have come to light the shaft may have been worked as far back as the early 1800s. A notice on the History Store advised the public that "The Colliery at Eshott, near Felton, is now working, and produce Coals of an excellent Quality, and in Quantity sufficient to supply a large demand and a moderate Price". It's difficult to see exactly what date it is from, but the site states it is 1803. I've double checked when the printer, Graham, was operating and found references to the 1820s.

https://www.historystore.co.uk/shop-ephemera/p/hs-3062-printed-notice-that-eshott-colliery-near-felton-is-now-working-1803

As identified in the Northumberland Name Books, the small rows over near Eshott Hall were occupied by pitmen working in the coal working identified. By the 1890s however the workings were extinct and all that was left was the original coal shaft against the lane.