ACS Chemistry for Life

Pytor Tchaikovsky’s ballet The Nutcracker is notable both as a testament to all that is magical about the holiday season and also as a dance production that requires a large number of young dancers to play a variety of roles. From children at the opening Christmas party, to the animals that accompany the dancers from Arabia, China, and Russia, ballet students aspiring to become stars get a chance every year to perform onstage.

One thing that all dancers need, from the youngest dancers to the highly accomplished Sugar Plum Fairy, is rosin. Each performer carefully steps into a tray of rosin to coat her or his ballet slippers before stepping out onstage.  The rosin provides traction on a slippery floor to make sure that dancers do not slip.

Rosin is made from the sticky resin of pine trees.  Distilling the original resin evaporates the volatile component, turpentine, leaving the rosin material behind.  Rosin may form crystals, but these are typically crushed into powder for subsequent reuse.

Dance is not the only performing art to benefit from the friction-inducing property of rosin.  String players customarily apply rosin to their bows so that the bow hair grips the strings more effectively, inducing more vibration.  The grade of rosin is specific to the type of strings so that bows used on the large strings of a string bass require the softest rosin.  Violin rosin may also be applied under the bridge of a banjo so that the bridge does not move during energetic playing.   

Rosin’s tackiness also helps improve grip or friction in numerous sports applications such as at the starting line of drag racing, for weight lifters, gymnasts, baseball pitchers, bowlers, and bull-riders.  

But in this season of light, music, and dance, let us celebrate how rosin contributes to the performing arts. 

More information about rosin can be found at http://www.violinstudent.com/rosin.html

This topic was suggested by Jennifer Acheson of Simsbury, Conn.