If you traveled in 10th or 11th century Spain, you’d see a sharp contrast in its regional pottery. During this high-water point in Muslim Andalusia’s power, the map had stabilized into a large southern Muslim nation and a strip of small kingdoms backed by the Pyrenees and the Atlantic.
Over the next few centuries, the two cultures blended, but at this point, they were about as distinctly different as they’d ever be. The northern Christian kingdoms were dominated by Visigothic aristocracy, the people who had fled the invaders leaving native tenant farmers behind. They were keenly aware of their aristocratic bloodlines, but the culture was still in the Dark Ages while southern Spain was fully Middle Eastern and medieval.
Northern pottery was simple, probably mostly made of coil technique. Unglazed pottery was the color of its clay; pottery glazed with the Roman lead process was yellow or green. This pottery was very functional: pitchers and bowls.
In the Muslim south, they were importing pottery from Alexandria. The court at Cordoba used pottery such as the northern kingdoms had never seen, using Iraqi methods of tin glazing, slip painting and double-firing. In fact, a new method had improved on even tin glazing for making fine white dishes. By the 11th century, they were mixing ground quartz with clay. The ground quartz is called “frit,” so we know this faux porcelain as fritware. The addition of frit lowered the temperature needed in a kiln, while fusing crystals in the clay and quartz into glass throughout the dish.
(Much later, during the Reconquista centuries, the two traditions began to fuse. An older art, that of painting/firing enamel onto pottery or glass, came into vogue. By the time northern kings were in control of central cities like Toledo and Madrid, Andalusian potters were ready to enamel heraldic coats of arms onto their dishes.)
The Islamic world, including Spain, was also developing pottery into perhaps the most useful form of all: tiles. Cordoba’s Great Mosque kept expanding as the Umayyad dynasty grew powerful, rich and secure. Its floor, ceiling and walls used many painted tiles. The full potential of plain-colored but geometrically-designed tiles was not yet part of Spanish, even Andalusian, architecture. It’s not clear that it was even developed yet in Persian-influenced Baghdad. The earliest eastern math-based tiles aren’t dated sooner than the 13th century; the Alhambra wasn’t built yet, either. (We’re only slowly sneaking up to the establishment of Cairo, after all.)
The use of tiled floor spread north much more rapidly than the Iraqi-pioneered techniques used in fine china. The floors in medieval French and English churches, monasteries and castle kitchens were often made of unglazed, natural-colored tile. Here, the tiles usually were natural-colored but simply shaped: squares, diamonds, triangles, hexagons. Much like the bathroom tile tradition we still see today.