The three terms are not exclusive: "Virgin Wool" refers to the raw material. It is wool straight from the sheep which has not been spun and woven before. Processed wool means it has been recycled: Old woollen rags are shredded and re-spun. "Worsted" refers to the spinning of the yarn. It is spun from the longest fibres and highly twisted to prevent all the little ends sticking out and making the fabric fluffy and soft (like a fabric suitable for an overcoat). The smoother the worsted yarns, the smoother the wool it produces, meaning, less fuzziness. "Tropical" refers to the weight. It means it is a lightweight cloth; it probably will be made worsted yarn, which was spun from virgin wool.