What terracotta is
Fired clay, left unglazed or finished with a glaze. The red that most people picture is the color of the clay itself after firing, and it varies with the earth it came from, which is why two terracotta floors from different regions are different colors before anyone chooses anything.
The word turns up both ways in searches, terracotta and terra cotta, and both mean the same tile. It comes from the Italian for baked earth and modern Italian writes it as one word; the split spelling is the older form and the one English kept.
Handmade and machine pressed
The two are made differently and they look it. A handmade tile is pressed into a mold and carries the marks of that: edges that are not quite straight, a face that is not quite flat, and a size that varies slightly across a box.
A machine pressed tile is dimensionally consistent and lays out predictably. Neither is the better product. The irregularity is what people buy terracotta for, and it is also the thing that has to be allowed for in the joint.
Natural and glazed terracotta
Most of this range is natural, which means the fired clay surface is what you see. It is porous, which is what unglazed fired clay is: what goes over it, and whether anything does, belongs to whoever lays the floor.
The glazed terracotta half is a different proposition. A glaze is a fired glass layer over the same clay body, so the surface is sealed by the firing and the color comes from the glaze instead of the earth. That is where the blues, greens and whites come from.
Terracotta outdoors
Terracotta has been an outdoor floor around the Mediterranean for a very long time, and it is asked about here more than any other single use. The material question is frost.
A porous fired clay takes up water, and water that freezes inside a tile expands. Whether a particular tile is rated for freezing conditions is published against that product, and it is the field to read before a terrace in a cold climate is specified. In a climate that does not freeze the question does not arise, and the outdoor tile range has the thicker pieces made for a base.
Terracotta sizes and thickness
The formats are small by modern standards: 6x6, 7x7, 8x8 and 4x4 lead, with 6x12 and 3x12 for the rectangles. A clay floor is a floor of many pieces, and the piece count per box runs high for that reason, often twenty or more.
Thickness splits by how the tile was made. The pressed and handmade pieces run 3/4 and 5/8 inch, thick enough to survive being made by hand; the glazed tiles are 3/8 inch, closer to an ordinary ceramic tile.
Color across a terracotta floor
Red dominates, with brown behind it and a smaller group in yellow, gray and beige. Within red the range is wide, from a pale sand to a deep rust, and a single floor carries a spread of it.
A terracotta floor is not uniform and does not become uniform. Boxes from one firing differ from boxes from another, which is the reason a floor is ordered in one go and a spare box is kept from the same run.
Reclaimed and related clays
The Spanish reclaimed tiles are the oldest thing in this part of the catalog: clay floors lifted out of buildings and sold on with a century of wear already in the face. Nothing new reproduces that, which is the whole argument for them.
Zellige is the closest living relative, another handmade fired clay from a different tradition, glazed and cut by hand so the edges ripple. It answers the same wish for a surface that shows it was made.
