It's a chronicle in rhyme of the history of the County of Holland from 689 up to the year 1305; this was republished starting in the year 1699 like the copy your friend has. It's an important book in Dutch history as it was one of the first we know of written in the native (Middle) Dutch instead of Latin. As far as antiques go it's not terribly unique; here in the Netherlands a brief search shows it's up for auction for €100 to €200.