Well-known types of chalcedony are carnelian, agate, and onyx. These include agate, jasper and rock crystal. Imitation dzi are created from materials other than agate or chalcedony. Cabochon adornments are sometimes made of cinnabar, agate, moonstone, or amber. Onyx is a variant of agate with black and white banding. These can include jade, agate, and jasper. Prehnite and agate amygdules are also plentiful island gemstones. Until the 18th century, the area was a source for agate and jasper. In Japan, percussion firemaking was performed using agate or quartz. Desert Rim, Puerco Pueblo, Blue Mesa, Crystal Forest, Giant Logs, Long Logs, and Agate House. Thunderegg is not synonymous with either geode or agate. The majority of modern agate cameos are carved with the aid of the Ultrasonic Mill. Malou is the Chinese name for the mineral agate. These drilled a hole with a core of agate inside the tubular drill. Tiny red spots caused by iron inclusion in the agate also increase the value.