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Hambergite is an often colorless gemstone named in honor of Swedish mineralogist A. Hamberg. While it is durable enough to wear in jewelry, hambergite is most commonly seen in specimen form. Rarely is a specimen flawless, and it can be easily confused with colorless quartz since they are similar in appearance. A unique characteristic of hambergite is its prefect cleavage that makes faceting into a gemstone very difficult for cutters.

Stichtite is purple, purplish pink to purplish red mineral first discovered at Dundas, Tasmania, Australia. It is most often opaque with a pearly or greasy luster. It is most often found in association with serpentine.

Among America's rarest and most stunning pearls, quahog pearls were first valued by Native Americans along the coast of New England. This non-nacreous calcareous concretion forms in colors from white to brown, to purple and lilac in round, button and teardrop shapes. Such pearls are typically collected by fishermen as a result of harvesting the meat of the shellfish.

Many minerals are copper ores, meaning they contain copper that could actually be extracted. Copper weathering is often involved in the unique coloration of specimens. Popular minerals that fall in this category include azurite, malachite and chrysocolla.

The tourmaline family consists of at least 14 distinct minerals, but the elbaite variety accounts for nearly all gem-quality tourmaline. It was named for the colored and colorless tourmalines found on the picturesque island of Elba off the western coast of Italy. Although best known in shades of green and red, elbaite can also be blue, purple, yellow, or colorless. Notable varieties of elbaite include rubellite, green tourmaline, indicolite, watermelon tourmaline, and Paraiba tourmaline.

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.

Generally transparent or translucent green, green-black, or grey-green in color, actinolite is named after the Greek word for "ray" or "beam," aktinos, referring to its fibrous nature. Actinolite also goes by the nickname 'ray stone' and is fairly prevalent worldwide.

The name staurolite comes from the Greek word stauros, meaning cross. Staurolite is prized for its twinned crystals that intersect at 60- or 90-degree angles forming x-like or perpendicular crosses. Specimens exhibiting these forms are highly prized by collectors. Sometimes referred to respectively as St. Andrew's and Greek crosses, as well as lucky cross, fairy stone or fairy cross, legend says the crystal crosses were created by the tears of fairies who could not help but cry when they heard of Christ's crucifixion. Staurolite is a metamorphic mineral that ranges from translucent to opaque in appearance and facetable gems are very rare.

Marble is a metamorphic rock formed under the influence of heat and pressure and consists of a mass of interlocking calcite or dolomite crystals. Pure marble is white, and some other marbles take their common names from their color or mineral impurities. Marble is often used for fine building material or sculpture, thanks to its beautiful appearance.

Topazolite is an Andradite Garnet that is yellow or brownish in color. It has a similar appearance to Topaz, and this resemblance inspired its name.

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.

Roman Glass is actual glass that has been buried for 2,000-years in mineral-rich soil. Archeological sites located near Jerusalem serve as the main source of Roman glass, notably because Israel once served as a major glass-making center. A thin layer of patina naturally forms on the glass as minerals in the soil react with the glass. The natural process of oxidation creates the various shades of blues and greens on the surface. As the coloration depends on the mineral condition to which the glass is exposed, each piece is unique.