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Named after the country, Afghanistan, where it was first discovered in a lapis lazuli mine in 1968, this rare and complex aluminosilicate forms blue crystals ranging from light aquamarine shades to saturated sapphire blue hues. The scarcity of gem-quality afghanite makes it a true collector's stone.

Seraphinite was named after Seraphim, the highest rank of angels in the Bible, due to the feather-like appearance of its chatoyant fibers. The stone usually has a dark green to gray color with silvery shimmer caused by mica inclusions. This unique, somewhat mystic-looking gem is often used for carvings, decorative pieces and cut as cabochons.

Named for its calcium content, calcite is one of Earth's more abundant minerals-- you've probably seen it many times and not known exactly what it was. It is found in marble and limestone, as well as other rocks used in industrial settings. Gem-quality calcite, however, takes on a quite different look. You may have seen colorless calcite crystals used as examples for double refraction, but it also forms as white, gray, yellow, pink and green gems. Material is often faceted or polished en cabochon, or carved into ornamental objects.

Chrysoberyl is the name of a mineral as well as three different gem varieties two of which are widely accepted as some of the most rare and valuable of all phenomenal gems. The gem commonly known as chrysoberyl is a yellowish-green, brownish-yellow, or colorless transparent to translucent mineral that is usually faceted into gems and generally considered a collector's stone. While not often set in jewelry, its characteristics make it ideal for such use. When chrysoberyl displays color-change properties, it is known as alexandrite, and when it exhibits chatoyancy, it is known as cat's eye chrysoberyl.

Indicolite is one of the most valuable and collectible of all elbaite tourmalines, with hues spanning from lighter to deep, intense blues. Cutting indicolite can be a task for even the most skilled of cutters, as it is strongly pleochroic and appears darker when viewed down the crystal. This factor must be taken into consideration when cutting, as a loss of transparency and brilliance can occur in darker specimens.

Arsenopyrite is the most common arsenic mineral, once known as arsenical pyrites. Its color is silver-white to steel-gray on freshly broken surfaces. It yields a garlic odor when heated and the fumes can be toxic. It may tarnish to form an iridescent layer. Although it has a reputation for being poisonous to humans, complex arsenic compounds are used in the treatment of disease caused by microorganisms.

Wurtzite is named after French chemist Charles Adolphe Wurtz. It was first described in 1861 after it was discovered in the San José Mine, Oruro City, Cercado Province, Oruro Department, Bolivia. It can be dark reddish brown, yellow to dark brown, to brownish black with a resinous or submetallic luster.

Black opal is the rarest and most valuable variety of opal. Black opal displays “play of color” and has a black, gray, dark green, dark blue, or blackish brown body color. Most black opal comes from Lightning Ridge and Mintabie, Australia, but it can also be found in Java, Virgin Valley, Nevada, and Wello, Ethiopia.

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.

Zandrite® is the brand name for a man-made glass with the unique ability to color change or color shift depending on the light it appears in. This occurs because the glass contains trace amounts of certain rare-earth elements like neodymium, lanthanum and cerium which react to different frequencies of ‘white light’. Typically, this means the color seen in indoor lighting will be a different hue or shade compared to that seen in daylight. The name was chosen by the late Jewelry Television Co-Founder Jerry Sisk and is an allusion to alexandrite, an expensive naturally occurring color-change variety of chrysoberyl. A scientist was the first to create, then realize the potential of this stunning gem (completely by accident). JTV offer Zandrite® in a variety of different colors, each offering a unique color-shift.

Ferberite is an iron-rich mineral commonly seen as a black to dark gray prism-shape specimens with metallic luster. At times it can exhibit weak magnetism and should not be confused with hematite.

Liddicoatite is a calcium-rich lithium species of tourmaline named in 1977 in honor of noted gemologist Richard T. Liddicoat. Gems may form in green, pink, red, blue and purple colors, sometimes with internal multicolor banding and zoning. Large crystals are often sliced to display their natural multicolor designs.