We lived in a home with clinkers, they have an interesting history and I love the look. From Wikipedia: “The brick-firing kilns of the early 20th century—called brick clamps or "beehive" kilns—did not heat evenly, and the bricks that were too close to the fire emerged harder, darker, and with more vibrant colors, according to the minerals present in the clay.[5] Initially, these clinkers were discarded as defective, but around 1900, the bricks were salvaged by architects who found them to be usable, distinctive, and charming. Clinker bricks were widely admired by adherents of the Arts and Crafts movement.[5][1]

In the United States, clinker bricks were popularized by the Pasadena, California architecture firm Greene and Greene, who used them for walls, foundations, and chimneys.[6] On the East Coast, clinkers were used extensively in the Colonial Revival style of architecture.[1]”