I have a propane lantern that the glass measures 3.25 X 3.25 and on the glass it has borosil with an r in a circle beside it, but no numbers so that we can get a new globe because it has broken. Anyone have any idea what the number is or where I can get a new globe for it.
From my experience (across multiple vendors!), the glass globes on propane lanterns are fairly standard sizes. It seems like there are two or three which are very common. Unless you have a real odd-ball size/style (and lacking a photo or more detailed description of what you have), you should be able to pick up a replacement off the shelf at your local Walmart or Target. Many other outdoor retailers (Academy Sports, Bass Pro Shops, Gander Mountain, etc) also carry replacements.
Take your dimensions with you to the store. My bet is that you'll find one which is compatible.