• A needle is essential for a phonograph to function.phonographe image by Christophe Fouquin from Fotolia.com
  
  The phonograph, a music-playing device first designed by Thomas Edison in 1877, had been the music player of choice from its invention to the late 1980s when digital technology replaced it. A phonograph needle, or stylus, is the part of the phonograph that contacts the record and transfers its vibrations to the rest of the phonograph system.
  
  

Copper and Steel

• The original phonograph needles were made of copper or steel made in soft, medium and loud tones. As their names suggest, the needles were designed to play the music with different volumes. Even though such needles transmitted sound of relatively good quality, they had to be changed after playing just two sides of a 78 rpm 25 cm disk. This wasn't very convenient and soon phonograph technicians replaced steel and copper with the more durable osmium.
  
  

Osmium

• Osmium is one of the hardest widely available metals on the planet. Osmium needles lasted about two times longer than copper and steel needles. Still, further improvements in needle durability was difficult to achieve using metals, and so gemstones came into use. Though more expensive than metal needles, needles made from gemstones lasted much longer.
  
  

Sapphire and Diamond

• Sapphire needles could play as many as 75 records before they needed a replacement. Needles made from diamond, the hardest naturally occurring material on Earth, were more expensive but lasted longer still--about two times as long as sapphire ones. Diamond and sapphire needles were still in use when the record players started to be phased out of production.