A clamshell bead tip, also known simply as a "clamshell," is a type of jewelry finding used to conceal a knot or bead in a design, for example, at the end of a beaded necklace or bracelet. It consists of two halves that can be opened and closed like a shell. The thread of the design, beads, or stringing material is passed through one half of the shell, then a knot is tied, a crimp bead is added, or a knot is made, and the other half of the shell is closed over it, hiding the knot or bead inside.
Clamshells are available in different sizes and materials, such as gold, silver, or plated metals, and can add a professional and finished look to quality jewelry.