For many guitar players a guitar pick is not really given the consideration it should, especially when it comes to how they affect sound. To prove this to yourself go find 10 different picks made from different materials and compare them on the same guitar. For the discrete player a guitar pick is as important as any other part of the guitar's sound puzzle. The variety of tones that can be obtained, just by changing picks, is surprising once a little attention is given to it.
Depending upon how thick and what material is used, plastic (or plasticized) type of picks can give a tonal range from "thin" to a thicker more robust tone as the pick itself thickens. Some of the more expensive picks like V-Pick and other high end companies have produced some great playing and sounding picks that don't give that "plastic" sound coming off of the strings. Plastics, being the texture that they are, often have a tendency to spin while playing and can be a distraction to some players.
With the variety of available woods out there, the possibilities are broad when it comes to wood guitar picks. In most cases wood is going to give you a sound that is natural and warm. The brightness is increased with the hardness of the wood being used. Personally, I think that Brazilian Rosewood makes one of the best wood guitar picks as it gives a perfect balance of natural tone and brightness.
Bone & Ivory
For a bright, punchy cut through the band natural sound, Bone or Ivory is a superior choice. Without being too bright bone or ivory will still have a natural ring to it but on the brighter side of thing.
Buffalo Horn has become our favorite material for making guitar picks and our best selling. It seems to have just enough warmth and just enough brightness to bring out the natural sound of the instrument without leaning too far to one end or the other. It's sound is somewhere between rosewood and bone with a strong hint of both.
There are two factors that can impact the play-ability of a guitar pick with regard to shape. Just as thickness has an impact so does the shape of the edge that hits the string. A sharper edge will sharpen the brightness and a more rounded edge will warm it up a bit.
After way too many years of compensating for spinning picks I finally got a wild hair and designed a pick that does't spin while playing. The objective was to use shape to counter act spinning and not a separate material on the pick as those materials tend to wear off. I wish I could say that it took weeks of research but the truth is that it took about 30 minutes to create a pick that fit the hand ergonomically. Typically we have to adjust our grip to fit the design of the pick and that is just bass-ackwards to me. Our result were hand made picks that you won't have to think about once you start playing.