Glossary A B C D E F G H I J K L M N O P Q R S T U V W X Y Z Term of the Day: Zinc white A common white pigment, zinc white is a brilliant white synthetically derived from the metal zinc. Jack-on-jack Layout pattern in which courses of tiles align vertically. Japan colors Concentrated oil-based colorants that are used for tinting alkyd paints and solvent-soluble glazes. Japan colors have an intense, flat color and will dry quickly. Jasper An opaque form of quartz that is usually yellow, brown, red or green. Joint The space between the adjacent surfaces of two components joined and held together by nails, glue, cement, mortar or other means. Joint compound A plaster-like substance used to fill seams and irregularities in drywalling, either the vinyl-based drying type, which hardens as the water medium dries, or setting type, which hardens by a chemical reaction that is catalyzed by water. Joint filler Sealant inserted between abutting ends of wallboard. Joint tape Paper or synthetic mesh tape about 3-inches wide that is used to bridge the seams between drywall panels.