Titanium is a transition metal element denoted by the atomic symbol Ti. It has an atomic number of 22 and the average atomic weight of its five natural isotopes is 47.88. It has a melting point of 3,020 ± 50°F (1,660 ± 10°C) and a boiling point of 5,948.6°F (3,287°C). The element occurs as a bright, lustrous, brittle metal or a dark gray powder. It is the ninth most common element with an abundance of 0.63% by weight in the earth's crust. Titanium has also been found in meteorites, in moon rocks, and in the sun and other stars.

The first mention of titanium appears in the writings of an English clergyman and amateur scientist, William Gregor (1761-1817). In 1791, Gregor described his analysis of a mineral obtained from a valley in the Menachan region of Cornwall. He reported that the mineral contained a "reddish brown calx" that he could not identify...