Waterbase clay (available at art and craft stores)
Rolling pin
Deeply veined leaf
Waxed paper

Roll clay to about 1/2 inch thick. Place the leaf on the clay. Cover with a piece of waxed paper. Roll again lightly so that leaf prints into clay. Cut into a square. Let it dry.

Instead of clay, you can use the recipe for Dough Ornaments.

Put magnet on back or put hole in for necklace.