You're lucky you get to make your own concrete. I live in a very...

You're lucky you get to make your own concrete. I live in a very sandy area and always struggle to find enough lime and clay to make Portland cement.
And wise choice about the glass panes - if you want float glass (and hey, who doesn't nowadays), it's quite hard to keep the molten tin bath at a constant temperature for long enough to get a nice flat surface on the glass. Definitely a "don't try this at home" one.