It is also mined in Asia, notably in Pakistan, Afghanistan, and Indonesia as well as in Sri Lanka and India, where some placer material suitable for gem use is found. === United States === Some fine gems and specimen material have been produced in the United States, with the first discoveries in 1822, in the state of Maine.
In 1850 Karl Friedrich August Rammelsberg described fluorine (F) in tourmaline for the first time.
In 1870 he proved that all varieties of tourmaline contain chemically bound water.
Dravite forms multiple series, with other tourmaline members, including schorl and elbaite. The name dravite was used for the first time by Gustav Tschermak (1836–1927), Professor of Mineralogy and Petrography at the University of Vienna, in his book Lehrbuch der Mineralogie (published in 1884) for magnesium-rich (and sodium-rich) tourmaline from village Dobrova near Unterdrauburg in the Drava river area, Carinthia, Austro-Hungarian Empire.
In 1889 Scharitzer proposed the substitution of (OH) by F in red Li-tourmaline from Sušice, Czech Republic.
The first documented case was in 1890 when Charles Russel Orcutt found pink tourmaline at what later became the Stewart Mine at Pala, California in San Diego County. === Brazil === Almost every color of tourmaline can be found in Brazil, especially in the Brazilian states of Minas Gerais and Bahia.
California became a large producer of tourmaline in the early 1900s.
During the early 1900s, Maine and California were the world's largest producers of gem tourmalines.
In 1914 Vladimir Vernadsky proposed the name Elbait for lithium-, sodium-, and aluminum-rich tourmaline from Elba Island, Italy, with the simplified formula (Li,Na)HAl6B2Si4O21.
In 1933 Winchell published an updated formula for elbaite, H8Na2Li3Al3B6Al12Si12O62, which is commonly used to date written as Na(Li1.5Al1.5)Al6(BO3)3[Si6O18](OH)3(OH).
The deposit was discovered in the 1970s, but is now exhausted.
The first crystal structure determination of a Li-rich tourmaline was published in 1972 by Donnay and Barton, performed on a pink elbaite from San Diego County, California, United States. === Chemical composition === The tourmaline mineral group is chemically one of the most complicated groups of silicate minerals.
Owned by Billionaire Business Enterprises, it was presented in Montreal, Quebec, Canada, on 14 October 2009. === Africa === In the late 1990s, copper-containing tourmaline was found in Nigeria.
Owned by Billionaire Business Enterprises, it was presented in Montreal, Quebec, Canada, on 14 October 2009. === Africa === In the late 1990s, copper-containing tourmaline was found in Nigeria.
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