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The term jade is used for jadeite and nephrite jade. For centuries the two materials were considered one and the same. It was not until 1863 that they were identified as different minerals with a similar appearance and properties. Jadeite jade is a member of the pyroxene group and is primarily composed of the mineral jadeite. Nephrite is a tough rock comprised of intergrown crystals of minerals from the tremolite-actinolite solid solution series, part of the amphibole group.

Rhodonite is an attractive mineral that is primarily known as an ornamental stone but is often seen in jewelry in the form of beads or cabochons. This mineral easily falls into the category of rare and exotic, making it highly prized by collectors of specimens and gemstones. Its name, derived from two Greek roots, means "rose-colored stone." Rhodonite, which is commonly found in massive or granular forms, is most often translucent to opaque in appearance. On rare occasion, transparent, gem-quality material may be found. Rhodonite's natural color ranges from pink to rose red to brownish red, often with blackish veins throughout.

The term saltwater pearl refers to the pearls that are harvested in marine environments such as bays, gulfs, and seas. South Sea, Tahitian, Akoya, and Sea of Cortez Pearls are the best known cultured saltwater varieties. Cultured saltwater pearls are more expensive than freshwater varieties.

September's birthstone has come a long way since the days when any and every blue stone was called a sapphire. Though its fame is shared with its "Big Three" counterparts ruby and emerald, sapphire has enjoyed a long run as one of the world's most beloved gemstones, earning itself a place of honor in crown jewels, royal accessories, museums, and even in modern royal engagement rings. Lest sapphire get too haughty, it has common uses as well. The rough polishing material on emery boards is made up of lower-quality corundum grains, strengthened with hematite, magnetite and quartz.

“Shell pearls” are imitation pearls. A mother of pearl bead nucleus is coated to resemble Tahitian, South Sea, or freshwater cultured pearls. They are an affordable alternative to their more expensive counterparts.

A mineral that often forms as an inclusion in quartz, dumortierite is usually fashioned as cabochons or beads for jewelry. While prized for its deep violet to blue colors, it may also be found in shades of pink, gray and brown. Named for French paleontologist Eugene Dumortier, dumortierite is an exotic gem that is durable, untreated, and rare.

George Frederick Kunz originally proposed the name starlite for zircon. The name starlight is sometimes used for blue zircon.

Named for the Latin word cerussa, meaning "white lead," cerussite is a lead carbonate mineral. It forms in several different crystal habits when carbonated water interacts with other lead minerals. Prized by mineral collectors for its twinned V-shape crystals that are transparent to translucent and are colorless to white, gray, brownish or greenish. Although too soft for jewelry, cerussite is occasionally faceted for collectors; however, it presents challenges to lapidaries due to its soft, brittle nature.

Named for the German biologist Lorenz Oken. Specimens often found as “cotton ball” formations because the crystals are straight and fibrous and they radiate out in orb like structures.

Lead glass or crystal glass is frequently called crystal. George Ravenscroft patented a process for making lead crystal around 1673 in London. The addition of barium oxide, lead oxide, potassium oxide or zinc oxide, to glass improves clarity, raises the refractive index, and increases dispersion. Famous crystal manufacturing houses are located in Austria, France, Ireland, and Sweden.

Goldstone is glass that contains myriad of tiny angular crystals of copper. First made in Italy, goldstone forms by reduction of particles of copper oxide within the glass during a process called annealing. Nothing in nature looks quite like glittering goldstone. Made in three distinct colors (blue, green and orange), goldstone is a tough and durable material that can be made in large pieces and fashioned into slices and objects of almost any desired size and configuration.

Apatite is the name for a mineral group as well as the generic term for many phosphates, but gem-quality apatite is a special gemstone found in a beautiful variety of colors. Apatite's various colors are often due to the presence of rare earth elements or natural irradiation. Because of its wide color range, apatite has often been mistaken for many other gemstones, including topaz, tourmaline, and various beryl varieties. Particularly rare in sizes over one carat, apatite is a relatively soft gem and when used in jewelry manufacture, is often set into more protective mountings that capture light yet safely display its beauty. The long-established sources for gem-quality apatite are Brazil and Mexico, but more recent African discoveries have thrust it into the spotlight once again.