Group 12 element by mass, and even the leanest concentrated deposits are at least 0.1% mercury (12,000 times average crustal abundance). It is found either as a native metal (rare) or in cinnabar (HgS), corderoite, livingstonite and other minerals, with cinnabar being the most common ore. While mercury and zinc minerals are found in large enough quantities to be mined, cadmium is too similar to zinc and therefore is always present in small quantities in zinc ores from where it is recovered. Identified world zinc resources total about 1.9 billion tonnes. Large deposits are in Australia, Canada and the United States with the
Ore Mountains sharply defined because the Ore Mountains, a typical example of a fault-block, descend very gradually. The topographical transition from the Western and Central Ore Mountains to the loess hill country to the north between Zwickau and Chemnitz is referred to as the Ore Mountain Basin; that from the Eastern Ore Mountains as the Ore Mountain Foreland. Between Freital and Pirna, the area is called the Dresden Ore Mountain Foreland ("Dresdner Erzgebirgsvorland") or Bannewitz-Possendorf-Burkhardswald Plateau ("Bannewitz-Possendorf-Burkhardswalder Plateau"). Geologically the Ore Mountains reach the city limits of Dresden at the Windberg hill near Freital and the Karsdorf Fault. The V-shaped valleys of