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Henry Platt, former president of Tiffany & Co., described tanzanite's discovery in 1967 as the most important gemstone find in 2000 years! A single 5-mile strip of land in Tanzania remains the only commercially viable source of this stone that has become one of the world's most sought-after and admired gems. Tanzanite is a relatively new gemstone in the world of gemology and jewelry. Though its history is brief, it is no less illustrious than many ancient gems. Tanzanite is a single-source gemstone that is a thousand times rarer than diamond, and it is only gaining popularity.

Found in several worldwide locations that are often zinc-rich environments, most hemimorphite crystals are white to grayish white, yellowish or totally colorless. But when the robin's egg blue hues are found, miners know they have hit a pocket of true gem-quality material. Not only is fine quality hemimorphite geologically scarce, but there are few locations that have the right combination of trace minerals that create this stunning blue color. This gem is often appreciated as natural specimens due to its almost bubbly botryoidal crystal habit.

Coral is the calcareous skeleton of marine animals known as coral polyps. The oldest known corals date back to 500 million years ago. In fossil coral the aragonite of the original structure is replaced by calcite or agate. The fossilization process preserves the ancient corals and makes very attractive cabochons that can be used in jewelry.

The Madeira name comes from the Brazilian word meaning ‘wood’ or ‘wood colored’. Most madeira citrine comes from heating amethyst with a brownish core to get the warm yellow or orange color. The primary sources come from the Brazilian state of Rio Grande do Sul, Uruguay, Zambia, and Madagascar.

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.

Poldervaartite can be found in a light orange-pink to milky-white color. High-quality poldervaartite specimens are prized by collectors and facetable material is rare.

Uvarovite is a highly desirable, yet widely unknown garnet species. Discovered in the 1830's in Russia, it was named in honor of Count Sergey S. Uvarov, a 19th century Russian statesman, scholar and avid mineral collector. Especially prized by collectors, uvarovite is hard to find anywhere, especially in sizes greater than 0.25 carats. Uvarovite ranges in color from medium to dark green and is best known for its granular, drusy masses which reveal well-formed dodecahedral or trapezohedral crystals under magnification.

Achroite refers to the colorless variety of tourmaline. An elbaite tourmaline variety, these gems are very rare and especially prized by collectors.

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.

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.

Nicknamed the "dragon stone," septaria has unique mineral patterns that resemble tree branches. Specimens are usually in the form of sliced nodules ranging from an inch in diameter to more than three feet across. They are estimated to have formed between 50 and 70 million years ago after periodic volcanic eruptions killed small sea life. The shells and carcasses of these creatures sank to the sea bed, where sediments accumulated around them to form nodules or balls of mud. When the waters eventually receded, the mud balls dried out and began to shrink and crack into the beautiful patterns that you see inside the septarian nodules.

One of the most desirable of all tourmaline varieties, rubellite is the pink to red variety of elbaite tourmaline, but crystals may also include brownish, orangey or purplish hues. Stones that exhibit pure red or slightly purplish red color are considered the most valuable. With the exception of ruby and red spinel, rubellite is the only other gem known to occur in such a rich, dark red color. Incredibly scarce, with 'eye clean' material even rarer, rubellite is one of those special gems that demands a place in your gemstone collection!