Gräflich Ortenburg were founded in 1946 and based in Tambach, Germany. They are known for the quality of their fat lava glazes and also square/rectangular forms that are glazed in a single colour gloss glaze.
Gräflich Ortenburg used a dark brown/red clay. Items are usually marked with a form number, occasionally there is an indication of size (usually by number (1, 2, 3) and occasionally in cm height). Some include a shield type mark (see photos below).