It's a fantastic beach, much like the majority of beaches in Thassos. However, we visited it after Paradise beach, and naturally, Paradise beach takes the cake when compared. Getting there can be a bit challenging for regular cars, but not impossible. It's better to drive a Jeep, Nissan X-trail, or something similar.
The gulf of the Marble beach appears to be deeper. There are large stones on the sides, and some of them can be quite slippery.
They have music playing, sunbeds, and umbrellas, but I'm not sure about the prices since we arrived on a Jeep beach safari.
We even had small shrimps giving us a foot peeling experience :))