We were originally scheduled to travel on La Amatista but two weeks before the trip I received an express letter saying that we were now traveling on La Turmalina. I love the jewel names, amethyst and tourmaline. The two ships are part of a fleet of four, built in the style of 19th century river boats, in the ship yard in Iquitos. La Amatista and La Turmalina can take 30 passengers and the other two, La Esmeralda and La Aquamarina take 17 and 24 passengers respectively. La Turmalina, our expedition riverboat is registered in Peru and operated by English speaking Peruvian Officers and crew. There can be up to 14 crew members. Our group of passengers numbered only 16 which was great for us - never rushed or crowded.