Density 21.5 (For Solo Flute). Composed By Edgard Varese and Edgard Var. For Flute (Flute). Woodwind Solo. Ricordi #Nr134978. Go to amazon.com Related posts Check expert advices for density 21.5? DescriptionWritten in January 1936, at the request of Georges Barrre for the inauguration of his platinum flute. 21.5 is the density of platinum.