Muscovado, panela, piloncillo, chancaca, jaggery and other natural dark brown sugars have been minimally centrifuged or not at all. Typically these sugars are made in smaller factories or "cottage industries" in developing nations, where they are produced with traditional practices that do not make use of industrialized vacuum evaporators or centrifuges. They are commonly boiled in open pans upon wood-fired stoves until the sugar cane juice reaches approximately 30% of the former volume and sucrose crystallization begins. They are then poured into molds to solidify or onto cooling pans where they are beaten or worked vigorously to produce a granulated brown sugar. In some countries, such as Mauritius or the Philippines, a natural brown sugar called muscovado is produced by partially centrifuging the evaporated and crystallizing cane juice to create a sugar-crystal rich mush, which is allowed to drain under gravity to produce varying degrees of molasses content in the final product. This process approximates a slightly modernized practice introduced in the 19th century to generate a better quality of natural brown sugar.