Italians told, that only certain breeds of heavy pigs can be used to make prosciutto (traditional Large White, Landrace or Dunroc). Pig legs rubbed with salt then refrigerated for about a week. Then added another thin layer of salt leading to another resting period of 15 to 18 days. The hams are then hung for approximately 80 days, in a special conditions room. After 80 days the hams have dried completely. Then Prosciutto are left to finish the curing process in dark cellar-like rooms. The curing should last a minimum of 12 months.
As for me, Prosciutto from Italy is better than Jamon from Spain.