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Monolith with bull, fox, and crane in low relief at Göbekli Tepe. The density of most stone is between 2 and 3 tons per cubic meter. Basalt weighs about 2.8 to 3.0 tons per cubic meter; granite averages about 2.75 metric tons per cubic meter; limestone, 2.7 metric tons per cubic meter; sandstone or marble, 2.5 tons per cubic meter.
A 1988 feasibility study found the mountain to contain approximately 298,000 tons of ore with a prediction of yielding 11,000,000 lbs of beryllium. [12] Round Top is known for containing rare-earth elements, including the largest deposit of heavy rare-earth elements in the United States, estimated at over 1 billion tons. [5]
(1.1 × 10 19 lb = 5.0 × 10 18 kg, modern value is 5.15 × 10 18 kg) and states that "compared with the weight of the globe this mighty sum dwindles to insignificance". [26] Absolute figures for the mass of the Earth are cited only beginning in the second half of the 19th century, mostly in popular rather than expert literature.
The Tetons and other north-central ranges contain folded and faulted rocks of Paleozoic and Mesozoic age draped above cores of Proterozoic and Archean igneous and metamorphic rocks ranging in age from 1.2 billion (e.g., Tetons) to more than 3.3 billion years (Beartooth Mountains). [16]
Per capita usage in the United States in 1996 was 8.7 metric tons per year. [7] Use, and therefore production of aggregate, is determined by the construction industry. Production in 2017 was well below the peak of 3.1 billion tons mined in 2006, during the height of the United States housing bubble. [8] [9]
The deposit is one of the largest iron reserves in the world. The reserves have been estimated at 6 billion tons, with an iron content of 2 billion tons. The phosphorus content of Minette rendered its industrial processing impossible for a long time, which changed with the introduction of the Thomas-Gilchrist procedure.
The use of rock has had a huge impact on the cultural and technological development of the human race. Rock has been used by humans and other hominids for at least 2.5 million years. [22] Lithic technology marks some of the oldest and continuously used technologies. The mining of rock for its metal content has been one of the most important ...
2.1 billion year old rock from North America showing banded iron formation, displayed in Dresden, Saxony, Germany. Banded iron formations (BIFs; also called banded ironstone formations) are distinctive units of sedimentary rock consisting of alternating layers of iron oxides and iron-poor chert. They can be up to several hundred meters in ...