The material called as tortoise shell is obtained from the breast shells of caretta caretta, a species of sea turtle. Tortoise shell is the most suitable material for the plectrum of tanburs. The plectrums made of such materials as bone, horn, ivory etc. are not suitable for the performance of the tanbur. In some of these materials, a surface as smooth as the tortoise shell cannot be obtained, the fibrous ones are scratched easily or cause electrification and this makes the performance of the instrument difficult.
For the tanbur, only a plectrum made of the tortoise shell can ensure a comfortable performance. The tortoise shell which is a rough shell is required to be cut at appropriate dimensions first and then its tilt should be adjusted. Afterwards, its smoothness is ensured with the help of water sanders at various thicknesses and it is made available for use.
Plectrum is a highly important tool in expressing the manner of the performance. Tanbur players have difficulties in performing the pieces with a plectrum which is incompliant with his own manner. Therefore, each tanbur player prefers to use suitable plectrums for their manners. The thickness values of the tortoise shell should e between 2,5 and 5 mm and the length of it should be 10 cm and 13 cm.
In order to prevent the plectrum from any damage, it is required not to hit it to hard surfaces, leave it at an area where it may be scratched and, if possible, to keep it inside a cover because the roughness which may be observed on the plectrum edges shadows the performance of the tanbur and causes unpleasant sounds.