Brunswick has been a manufacturer of many types of merchandise. In regard to Duckpin bowling balls, I’ve seen the Brunswick Fireball and the Brunswick Mineralite (there may be another one, but it slips my mind at the moment). But, Brunswick also manufactured a “Mineralite” ball for Lawn Bowling, as shown below.
Shown below is a comparison between the Lawn Bowling ball and a Duckpin ball. You’ll notice that the Lawn Bowling ball is more of an oval shape, whereas the Duckpin ball is completely round.