When polished en cabochon, they display a silver four-ray star. A rare variety of diopside known as 'star diopside' contains fine prismatic crystals of magnetite. Its green color is often bright enough that it is used as a substitute for emerald. Diopsideĭiopside often occurs as a bright green, translucent to transparent gem that is cut into faceted stones, cabochons, and beads. These cabochons are approximately 8 millimeters across and we paid less than $30 for the pair. They are slightly magnetic, indicating that the silk is probably magnetite crystals. Star Diopside: A black star diopside cabochons exhibiting four-ray stars. The beads range in size between 3 and 5 millimeters in diameter. Ancient people discovered this property and used jadeite to make weapons, impact tools, and cutting tools in parts of the world where the mineral was easily found as stream pebbles, cobbles, and talus.Ĭhrome Diopside Beads: Rondelle-shaped beads cut from bright green chrome diopside mined in Russia. In Asia, high-quality jadeite can sell for prices that rival diamonds on a per-carat basis.Īlthough jadeite is not a mineral of exceptional hardness, it is a mineral of exceptional tenacity - which means that it is a durable material that resists breaking. Jadeite is the most important gemstone in China, where it has been held in highest esteem for thousands of years. Both of these minerals are used to produce cabochons, beads, bangles, small sculptures, and a wide variety of utility items. Jadeite (a pyroxene) and nephrite (a member of the amphibole mineral group) are the only two minerals that can legally be called 'jade' in commerce. This photo was taken by John Hill and is distributed under a GNU Free Documentation License. Mayan jadeite: Hand-made Mayan jadeite pectoral from the Mayan Classic period.

Pyroxene and feldspar ternary diagram