Complex sentence: Of course no such thing exists: gold is too malleable to use for a rivet; like many urban legends the "golden rivet" is perpetuated for the amusement of "old salts" at the expense of the gullible.
Split into simpler sentences: Of course no such thing exists: gold is too malleable to use for a rivet. Like many urban legends, the "golden rivet" is perpetuated for the amusement of "old salts" at the expense of the gullible.