Severoceske Doly a.s.(SD). The Group principal activity is the coal mining. The Group's main products are lignite and mining by-products such as kaolin, clay, sand and humic acid salts. The Group's main customer is CEZ a.s., the country's biggest electricity and heat distributor. The sales of rough powder rose up by 11.4% , sorted coal by 7.12% and sales of industrial mixes went up by 1.1% during the year 2001. The Group is also involved in transportation and information technology activities. Lignite accounted for 95% of 2001 revenues and other, 5%.