Opus

Coober Pedy is a town in northern South Australia. The town is known as the opal capital of the world because of the quantity of precious opals that are mined there. It is also famous for most of the residents living below ground, mostly in old mines refurbished, due to the scorching daytime heat.

Diatoms are a major group of microorganisms found in the oceans, waterways and soils of the world. Living diatoms number in the trillions: they generate about 20 percent of the oxygen produced on the planet each year; take in over 6.7 billion metric tons of silicon each year from the oceans in which they live; and contribute nearly half of the organic material found in those oceans. The shells of dead diatoms can reach as much as a half mile deep on the ocean floor; and the entire Amazon basin is fertilized annually by 27 million tons of diatom shell dust transported by westerly transatlantic winds from the bed of a large dried up lake once covering much of the African Sahara. Diatoms are unicellular; they can live alone or form colonies, taking shapes such as ribbons, fans, zigzags, and stars.

Deadvlei is a white clay pan located near the more famous salt pan of Sossusvlei. Dead Vlei is surrounded by the highest sand dunes in the world, the highest reaching 300-400 meters. The clay pan was formed after rainfall, when the Tsauchab river flooded, creating temporary shallow pools where the abundance of water allowed camel thorn trees to grow. When the climate changed, drought hit the area, and sand dunes encroached on the pan, which blocked the river from the area. The trees died, as there no longer was enough water to survive. There are some species of plants remaining, adapted to surviving off of the morning mist and very rare rainfall. The remaining skeletons of the trees, which are believed to be about 900 years old, are now black because the intense sun has scorched them. Though not petrified, the wood does not decompose because it is so dry.