Madagascar

Our Mineral of the Month for September will be microcrystalline quartz (chalcedony) in the form of petrified wood. These specimens from Madagascar consist of an extremely fine-grained chalcedony that has preserved the original structures of the wood in extraordinary detail and have taken a fine polish. Our specimens, which are 225-million-year-old fossils of trees of the coniferous genus Aurucaria, have base colors of off-whites to dark browns and also exhibit flashes of yellows, reds, and even greens and blues.