Thanks Derek. I'll have a browse of their site. I'm learning fast and all your replies and comments are invaluable for furthering my knowledge and education. Had another weight in the post this morning, a Selkirk weight, quite a large one, and on the faceted side is engraved 'Thermomax' with the Company logo above and 91 etched on the base. Have been on Thermomax's website and emailed them with an image to hopefully find out more details.
I'm going to a large local antiques fair on Saturday and will be looking out for any quirky signed weights, you can find some nice cheap ones at these.