NPT TGMSFC618 6" x 18" Marble Splitface Corner Tundra Gray. The timeless elegance of Marble can transform any outdoor area into a beautiful, inviting space. Swirls and striations form the distinct pattern only found in Marble, while the cool tones enhance the natural serenity of any open-air setting. Tundra Gray Marble captures the intricate patterns of frosted, icy plains.