Depends on the specific pliers.
Good ones will typically be made out of a high carbon grade steel and heat forged to make it stronger than typical metals that one would want to cut.
Metal
Pliers are made of steel. There are plastic pliers for children too.
The best pliers for making chainmail are flat nose pliers and needle nose pliers. These tools are ideal for gripping and manipulating small metal rings used in chainmail crafting.
if i was to remove metal i would use pliers
Use Small .99 Pliers
Pliers with a special shape in the head (mine have 3 shapes) that compress a 'crimp' (a small metal tube) onto a wire.
Early plier-like devices were first used in ancient times to handle hot objects and coals in a cooking fire. When metalworking developed, pliers were used to handle the hot metal at the forge. The first pliers were made from wood, later from bronze.
Pliers are made of steel and as such will conduct heat -and electricity! However pliers whose handles are covered with rubber or plastic sleeves will be insulated against heat.
Steel with rubber insulated handles
To create a DIY metal ring at home, you will need metal wire, pliers, a mandrel or cylindrical object to shape the ring, and a file to smooth the edges. Cut a piece of metal wire to the desired length, wrap it around the mandrel to form a circle, and use the pliers to secure the ends together. File any rough edges to finish the ring.
They use small pliers to twist the metal around a small chunk of hair.
Usually I use metal, beads, pliers, wire cutters, beading wire, and crimp supplies.