Rex Partridge's article about Byfield & Charwelton Iron Ore quarries is slated for publication in the June edition of Steam Days. The title is 'Byfield & Charwelton Related By Stone'.
Just to add to this, I found footage of Ivo Peters visit to Byfield quarries on Youtube
It shows 'Cherwel' entering the exchange sidings with wagons, photographers can be seen on the SMJ. There is also a scene at the shed with 'Sir Berkley. This is within the first 3 to 4 mins of video.
well worth watching the whole of the video.