Hi Everyone
For the record, Croesor was acquired by the Ffestiniog Slate Company in the early 1970's with a view to working it then. The pumps were still on, electric to the head of and down the main incline and lights in the chambers. Planning applications failed, however, on both access and tipping, though most of the latter could have been underground. A similar application for Rhosydd failed for the same reasons. After the failure of the application, Croesor was stripped out, the incline winches, mill roof beams etc. went to Gloddfa Ganol and the site was (presumeably) sold off again.
Regarding the ownership business. I'll quote myself (!):
in 1970 the Oakeley Quarries as such were closed and their deep underground workings scrapped and allowed to flood up to the drainage levels. The site was sold to Glyn Williams, a local coal merchant, haulage and plant hire firm owner. He continued the open workings of the old quarry as the Ffestiniog Slate Company, retaining sections of the underground workings above the flood waters for special quality slate and as reserves of rock. This activity took place principally in the Lower Quarry, although roads were constructed throughout the site to enable modern tracked vehicles and lorries to reach all parts of the site where there might be workable slate and for maintenance purposes. For a while the Upper and Middle quarries languished, but soon afterwards the old Middle Quarry slab producing mill was put into service for architectural and slab work by Wil Roberts, Glyn Williams’ son in law, and by 1974 this formed the nucleus of the new Gloddfa Ganol company, named after the welsh for Middle Quarry. As trade developed other slate quarries were taken over and a trading organization was set up as The Ffestiniog Slate Group.
Gloddfa Ganol, as well as being a productive member of the group, was intended from the start to tap the tourist trade and the increasing interest in our industrial past. It’s formal title was Gloddfa Ganol – Ffestiniog Mountain Tourist Centre. From 1974 until the 1990’s working there continued in parallel with tourism, but for a number of reasons – recession being a major contributing factor – the whole of the Ffestiniog Slate Group of companies was bought up by McAlpines who had been working the Penrhyn Quarry at Bethesda since the late 1960’s. They closed down the tourist side of the business and proceeded to radically re-organise the open workings and production methods in line with their long experience at Penrhyn, introducing modern geological surveys, Health & Safety analyses and other large scale methods of working."
For people who like floor heights I've put a list of oakeley/cwmorthin's on Miles' site.
More answers to queries when I get a mo.
Grahami
The map is the territory - especially in chain scale.