Soapandwine is absolutely correct!
Here it says that "a real savon de Marseille consists of 72% oil. It must be of vegetable oil or a mixture of vegetable oils or olive oil, but of the same percentage. (I believe it doesn't say the oils must be of equal proportion, but the total of the oils must be 72% of total weight). Depends on the oils used, the color of the soap varies. It must not contain animal fats or preservatives".
The weight stamped on the soap is its weight when freshly cut, not fully cured.
http://www.familleaunaturel.com/reconna ... marseille/
And according to this site, the ones made with coconut and palm oils are cream and with olive, coconut, and palm oils are green. (Note: The green color comes from the olive oil, not additives or clay or colorants. In fact, no additives are allowed other than a tiny drop of essential oil).
http://www.avignon-et-provence.com/savo ... Jk5g_UjLec
Most of the French websites stated that the only oils used are coconut, palm, and olive. Olive pomace is allowed. Marius Fabre added shea butter to some of the small soaps but there is no mention of sea water.
Savon de marseille actually originated from Aleppo soap, a 100% olive and bay laurel oil hot-process soap from Syria ...
http://www.alepposoap.com/presentation.html