This is fixed now, thank you royfellows for pointing it out and also to Vanoord for the realisation that the list was split into two which led to working out what the problem was.
Basically I'd forgotten to do a trim command on that last big batch of mines that were imported (from royfellows and Roy Morton) so some of the mine names had leading spaces.
Hence the mines with names that started with a space came first and then the mines with names without a leading space so it ended up with anomolies like:
_Zebeddee Mine
Alphabetti Shaghetti Mine
I've also done the A-Z on the Show all Mines page, it retains the facility to toggle between mines with content and mines without content.
http://www.aditnow.co.uk/list-uk-mines-quarries/ Note, the mines with content, whilst a shorter list, may still be slower to load.
This is because the full list, whilst longer, is a basic return of the mine name, sheet and mineral/product type. Whereas for the mines with content, the system has to go off and count the albums, the photos in those albums, the documents, the notes and votes, and then present all this information for each and every mine.
However I think the A-Z list is an improvement and makes the full mine list much more responsive.
my orders are to sit here and watch the world go by