I make all my silver leaves from real leaves.  I choose a suitable leaf and cover it with many layers of Silver Clay (for those who are unfamiliar with this, it is tiny particles of pure Silver which is bound in an organic binder). When I am satisfied that there are enough layers, the leaf is then fired in a kiln, burning away the leaf and leaving an exact imprint of the leaf.  Each piece is unique and can take many hours to make.