In dry pressing, spray-dried powder is compacted in a steel mould by a hydraulic press at several hundred bar. The pressed tile is strong enough to be conveyed, dried, decorated and fired without a support.
Most floor and wall tiles are made this way. Standards identify dry-pressed tiles with the letter B, as in BIa for porcelain. Continuous compaction lines, which press the powder between belts, are used for large slabs.