Paper marbling Turkish and Persian, which literally means Frankish. Historic forms of marbling used both organic and inorganic pigments mixed with water for colors, and sizes were traditionally made from gum tragacanth ("Astragalus" spp.), gum karaya, guar gum, fenugreek ("Trigonella foenum-graecum"), fleabane, linseed, and psyllium. Since the late 19th century, a boiled extract of the carrageenan-rich alga known as Irish moss ("Chondrus crispus"), has been employed for sizing. Today, many marblers use powdered carrageenan extracted from various seaweeds. Another plant-derived mucilage is made from sodium alginate. In recent years, a synthetic size made from hydroxypropyl methylcellulose, a common ingredient in instant wallpaper
Purple is a spectral color. On the CIE xy chromaticity diagram, violet is on the curved edge in the lower left, while purples are on the straight line connecting the extreme colors red and violet; this line is known as the line of purples, or the purple line. During the Middle Ages, artists usually made purple by combining red and blue pigments; most often blue azurite or lapis-lazuili with red ochre, cinnabar, or minium. They also combined lake colors made by mixing dye with powder; using woad or indigo dye for the blue, and dye made from cochineal for the red.