Welsh Slate Company
Purchased Samuel Holland's original lease in 1825 and expanded quarrying at Rhiwbryfdir into what became the Lower Quarry, one of the three operations later forced into a single combined business, Oakeley Quarry, after the catastrophic rockfalls of 1882-83.
Mines operated
| Mine | Region | Years |
|---|---|---|
| Oakeley Quarry | Gwynedd | 1825–1883 |
Record created: 22 August 2026