There is a rule about using silver metal clay that says 10 - 80 - 10. This is 10 of the time making the piece, 80 of the time sanding and finishing it and then 10 firing and final finishThsi implies that the most of your activity should be about preparing the dried silver metal clay for firing. Sanding edges is a major part of achieving a quality finish and these little sponge sanding pads are ideal for the job They can be washed out after use ready for next time and last for a considerable amount of time I have had mine for nearly a year