Generally leaching is the dissolution of elements from a surface into the surrounding fluid medium. For the soldering community, the term applies to the action of liquid solder dissolving metals such as silver from surfaces. A particular case where leaching has been observed is the chip ceramic capacitor, whose inner terminals are typically of silver alloys held together with a matrix of glasses. Solder can leach the silver to such an extent that electrical connection is no longer made. Solutions to the problem include both using silver alloys with platinum and palladium to reduce the solution rate, and providing a â€˜nickel barrierâ€™ plating on top of the original metallising. For most purposes, this barrier layer is supplied already solder plated.