I've just put together a spread sheet for calculating L.E.C. (I know; its a guide not gospel) Is anyone willing to share any additional expansion values for things like strontium, or any other potentially useful ingredients, beyond what's listed in 'Modern Glass Practice' and 'Glass Notes IV'? Or have a suggestion of where to look for such additional values? Thanks in advance.
P.S. the original E&T values were published in 1927 in the Journal of the American Ceramic Society volume 10, pg. 551. It's a well written piece of history.