Two or more pure substances can be mixed together to form a mixture. An example of a mixture of two compounds is alcohol and water. An example of a mixture of elements and compounds is air. The major components of air are hydrogen, oxygen, nitrogen and carbon dioxide. The substances in a mixture can be separated physically via such methods as filtration or chromatography.
Enigma is a German musical project founded in 1990 by Romanian-German musician and producer Michael Cretu. Cretu had released several solo records, collaborated with various artists, and produced albums for his then wife, German pop singer Sandra, before he conceived the idea of a New Age, Worldbeat project.
The Romanian-born Cretu conceived the Enigma project while working in Germany, but based his recording studio A.R.T. Studios in Ibiza, Spain, from the early 1990s until May 2009, where he has recorded all of Enigma's studio releases to date. Cretu is both the composer and the producer of the project. His former wife, pop singer Sandra, often provided vocals on Enigma tracks.