Fishing sinker weight acting as barbs. Claw sinkers are used in surf fishing on sandy bottoms with strong currents, mainly to prevent the sinker from getting carried off with the current. Upon casting a claw sinker, the line is briefly tugged so that the claws will dig themselves into the sand, allowing the rig to stay in place. An ideal material for a fishing sinker is environmentally acceptable, cheap and dense. Density is desirable as weights must be as small as possible, in order to minimize visual cues which could drive fish away from a fishing operation. In ancient times as well
Bullet tin or typesetter's lead (used to mold Linotype) works very well. For even higher-speed bullet use, jacketed coated lead bullets are used. The common element in all of these, lead, is widely used because it is very dense, thereby providing a high amount of mass—and thus, kinetic energy—for a given volume. Lead is also cheap, easy to obtain, easy to work, and melts at a low temperature, which results in comparatively easy fabrication of bullets. Poisonous bullets were a subject to an international agreement as early as the Strasbourg Agreement (1675). The St. Petersburg Declaration of 1868 prohibited the use