What's "take a rub" mean?

Native speaker’s answer
Rebecca
It's actually "rubbing," not "rub." A "rubbing" is an impression of a design, shape, or texture that is made by laying a piece of paper over the object and using wax, pencil, or chalk to rub over it. Ex: I made a rubbing of a cool fossil I found. Ex: I took a rubbing of the fern I found on my nature walk.