The Wallaroo Harlequin Stone Quarry located on the Yorke Peninsula produces a very colourful and strong decorative stone. The rock was formed millions of years ago when hot fluids from nearby granite changed the older rocks, creating a mix of green, red, orange, and black colours with sparkling veins of quartz. Because of its striking appearance and toughness, Harlequin Stone is cut, polished, and used for things like flooring, benchtops, wall cladding, and other building or design features. It also can be used for landscaping and garden rocks. It is well known both in Australia and overseas for being beautiful, durable, and unique to the Wallaroo area.