Clay was admixtured with 1, 2, 3 and 10% of waste sludge precipitated from lead electroplating fluoroborate electrolyte. The sludge contained, besides 60.7% of lead, 3.7% of fluorine. Small standardized ceramic bricks were burnt at 980°C and then tested for physical and mechanical features (contraction, water soaking, freeze resistance, compressive strength) and for leaching with water saturated with carbon dioxide. The tests showed that 1% of added sludge did not change properties of ceramic bricks and leaching of lead and fluorine is not hazardous, while the larger admixtures result in spoiling of quality features. On burning fluorine is emitted to exhaust gases.