The city of Atlanta, Georgia, in Fulton County, was an important rail and commercial center during the American Civil War. Although relatively small in population, the city became a critical point of contention during the Atlanta Campaign in 1864 when a powerful Union army approached from Union-held Tennessee.
Rare-earth compounds containing lanthanum are extensively used in carbon lighting applications, especially by the motion picture industry for studio lighting and projection.
Lanthanum is considered a rare earth metal because the process to mine it is difficult, time-consuming and expensive. Lanthanum is rarely the dominant lanthanide found in the rare earth minerals, and in their chemical formulae it is usually preceded by cerium. Rare examples of La-dominant minerals are monazite-(La) and lanthanite-(La).