I want to fit some glass shelves in my kitchen between two small wall cupboards. I have 4 shelves but they are just too long to fit. I am unsure what type of glass they are, they were used as shelves before so should be toughened in some way. Is there a way to discover what type of glass they are and if/how I can shorten them to fit? The shelves I have are around 1 metre and the gap is 88cm taking into account the brackets I'm using. The shelves are 6mm thick, clear with green edges. Will add pics as soon as I work out how...... TIA, Drew.