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Sapphirine was so named because of its resemblance in color to blue sapphire, even though the two minerals have completely different chemical, optical and physical properties. Sapphirine is very rare, with small gems only faceted for collectors. This gem is know for blue color, but occasionally forms in a red-orange variety.

Very distinctive in appearance, cavansite is a rare, not to mention strikingly beautiful, blue mineral. Its name is derived from its composition: calcium, vanadium and silicon. Only discovered in the 1960's in Oregon, cavansite is highly sought after by mineral collectors across the globe. Found in a scant few locales, cavansite sources include Brazil, India, New Zealand and Oregon USA. It is renowned for its stunning deep blue hues that are sometimes vivid enough to be described as "electric blue."

Dioptase is a bright emerald-green or blue-green gemstone noted for the visibility of internal cleavage planes. The transparent to translucent dioptase gemstone is uncommon and generally found in desert regions. Rivaling the beauty of emerald, dioptase is typically sold as specimens and gemstones are rarely seen, especially in sizes over 1 carat.

Haüyne is an extremely rare mineral and even rarer gemstone. Its bright blue color is common for this stone, but it can be found in white, gray, yellow, green, and pink colors too. Lazurite the sulfur rich variety of haüyne is what gives lapis lazuli its blue color. The best-known specimens have been found in Eifel Mountains of Germany.

While it was once just a collector's gem, spessartine, an orange variety of garnet, made its move into the mainstream during the 1990s when new deposits were discovered in Africa. Like most garnets, spessartine is typically untreated, so the beautiful color and clarity that you see in them is just as nature created it. Spessartine garnet is named after its first discovery in Spessart, Bavaria, in the mid 1800's.

Marcasite is a polymorph of pyrite. It has the same chemistry, but a different crystal structure. In the jewelry trade, the names pyrite and marcasite are often used interchangeably. Marcasite is often cut and polished in a cone or pyramid shape and pave set between sterling silver beads to enhance their brilliance.

Danalite is a very rare brown, yellow to pink-red colored mineral named for the American mineralogist James Dwight Dana in 1866. Danalite has a limited number of global sources, including the New England states of Massachusetts, Rhode Island and Delaware.

Vanadinite derives its name from the vanadium contained within its chemical formula. Well-formed mineral specimens are prized by collectors. It comes in red to brown, orange, and yellow. It rarely appears colorless or white. Fine mineral specimens come from Morocco and Namibia.

Beautiful and rare, sillimanite is named for the famous American geologist Benjamin Silliman. It was relatively unknown until a substantial find was discovered in Orissa, India, in the 1990's. Sillimanite is not only scarce, but it also difficult for miners to identify and is problematic for cutters. These three attributes ensure that sillimanite remains a true exotic gemstone. Sillimanite ranges from colorless to white, brown, yellow, blue, and green in color and consists of compact fibrous material that have a silky luster. A polymorph of kyanite and andalusite, sillimanite makes an exciting addition to any gemstone collection.

Bismuth is rarely found naturally in its elemental form (even less commonly than platinum), but lab-grown crystals are gaining in popularity for their unique geometric formations (hopper crystals) and phenomenal iridescence. Bismuth is a silver-white metal, but an oxide layer forms immediately when crystals make contact with air. This produces an array of colors similar to that of a soap bubble or oil on water. The different colors are dependent upon the thickness of the oxide layer, which determines how light is reflected off of the surface creating a striking rainbow effect.

Diaspore is beautiful and exotic in a soft, subtle manner. It is also one of the lesser known of the color-change gemstones. Some of the finest examples of gem quality diaspore are found in Turkey's Anatolian Mountains, but it can be found in numerous places around the globe. A rising star in fine jewelry, it's easy to fall in love with its sparklingly brilliant, tranquil earthy colors.

Fossils are the preserved remains or traces of long dead algae, animals, and plants. The oldest known fossils are 3-billion-year-old ancient algae. The word fossil comes from the Latin word fossus which translates to “having been dug up”. For a fossil to form, an organism, or the trace of that organism, must be buried by sediment. Over long periods of time the remains will become preserved when the surrounding rocks alter the chemical and mineral composition of the remains.