Quite by chance I stumbled across your quest for information about the Izons. We are going to the Izons/Cast Hollow-Ware annual shareholder's meeting tomorrow. I know that there used to be a Lamb who was a shareholder and I will ask if they would allow me to pass contact information to you.
The founder of Izons was John Izon born in 1735 and died in 1814. I tried to send to the e-mail address given on Genealogy. com, but this failed.
I hope this has been of help. Please feel free to use my e-mail address firstname.lastname@example.org.