Riga vs Cobalt

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Riga (; Latvian: Rīga [ˈriːɡa] (listen)) is the capital of Latvia and is home to 627,487 inhabitants (2020), which is a third of Latvia's population. Being significantly larger than other cities of Latvia, Riga is the country's primate city. It is also the largest city in the three Baltic states and is home to one tenth of the three Baltic states' combined population. The city lies on the Gulf of Riga at the mouth of the Daugava river where it meets the Baltic Sea. Riga's territory covers 307.17 km2 (118.60 sq mi) and lies 1–10 m (3 ft 3 in–32 ft 10 in) above sea level, on a flat and sandy plain.Riga was founded in 1201 and is a former Hanseatic League member. Riga's historical centre is a UNESCO World Heritage Site, noted for its Art Nouveau/Jugendstil architecture and 19th century wooden architecture.

Riga was the European Capital of Culture in 2014, along with Umeå in Sweden. Riga hosted the 2006 NATO Summit, the Eurovision Song Contest 2003, the 2006 IIHF Men's World Ice Hockey Championships and the 2013 World Women's Curling Championship. It is home to the European Union's office of European Regulators for Electronic Communications (BEREC). In 2017, it was named the European Region of Gastronomy. In 2016, Riga received over 1.4 million visitors. The city is served by Riga International Airport, the largest and busiest airport in the Baltic states. Riga is a member of Eurocities, the Union of the Baltic Cities (UBC) and Union of Capitals of the European Union (UCEU).

Source: Wikipedia

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Cobalt is a chemical element with the symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal. Cobalt-based blue pigments (cobalt blue) have been used since ancient times for jewelry and paints, and to impart a distinctive blue tint to glass, but the color was later thought to be due to the known metal bismuth. Miners had long used the name kobold ore (German for goblin ore) for some of the blue-pigment-producing minerals; they were so named because they were poor in known metals, and gave poisonous arsenic-containing fumes when smelted. In 1735, such ores were found to be reducible to a new metal (the first discovered since ancient times), and this was ultimately named for the kobold. Today, some cobalt is produced specifically from one of a number of metallic-lustered ores, such as cobaltite (CoAsS). The element is, however, more usually produced as a by-product of copper and nickel mining.

The copper belt in the Democratic Republic of the Congo (DRC) and Zambia yields most of the global cobalt production. World production in 2016 was 116,000 metric tons (114,000 long tons; 128,000 short tons) (according to Natural Resources Canada), and the DRC alone accounted for more than 50%.Cobalt is primarily used in lithium-ion batteries, and in the manufacture of magnetic, wear-resistant and high-strength alloys. The compounds cobalt silicate and cobalt(II) aluminate (CoAl2O4, cobalt blue) give a distinctive deep blue color to glass, ceramics, inks, paints and varnishes. Cobalt occurs naturally as only one stable isotope, cobalt-59. Cobalt-60 is a commercially important radioisotope, used as a radioactive tracer and for the production of high-energy gamma rays. Cobalt is the active center of a group of coenzymes called cobalamins. Vitamin B12, the best-known example of the type, is an essential vitamin for all animals. Cobalt in inorganic form is also a micronutrient for bacteria, algae, and fungi.

Source: Wikipedia