There are three main beaches in Tropea, though really, it's one line of sand interrupted--once by a group of rocks that you can walk around, and once by an island with a disused monastery on it. It's a bit like Tenby with sunshine!
The sand is golden and soft, but take care of the water--Calabria's coast can be pretty violent. The slope of the beach under the water is pretty steep and if there have been any storms anywhere nearby, the waves get really strong.
This bit of Calabria is described by the locals as the "purple coast," and the water is a beautiful inky blue. Contrast that with the golden sand beaches and sandstone cliffs and you have a truly beautiful spot for a doze in the sun.