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Moldavite is a silica rich tektite found near the Moldau River in Czechia. Moldavite is a natural glass formed as a result of a meteorite impact with the earth. It was first discovered in the late 1700’s in what was then known as western Moravia. The colors of moldavite range from yellowish green to green and brownish green.

Coral has been prized throughout history for its natural beauty. Like pearl, coral is also an biogenic gem consisting of more than 90% calcium carbonate. All coral consists of the remains of skeleton-like support structures that were built by colonies of very small marine animals, known as coral polyps. Proteinaceous coral differs from calcareous coral because it is made up of strong keratin proteins.

Limestone is composed mainly of calcite and occurs in thick extensive, multiple layers. It is formed in shallow seas from a combination of calcium carbonate or the accumulation of shells and skeletons of calcareous marine organisms. Limestone is abundant and is very important commercially as it has a number of different uses as a building stone, cement and as a raw material in the glass manufacturing process. Limestone that is recrystallized under heat and pressure becomes marble.

Astrophyllite is golden-yellow to dark brown and usually forms as bladed crystals radiating from a common center. It gets its name from the Greek astron, meaning "star," and phyllon, meaning "leaf." It may also be translated as "star sheets" because of the interwoven star shapes that crystals sometimes form, and because of its strange luster, which can be metallic or pearly. Although there are occurrences of astrophyllite around the world, some of the finest crystals come from remote mountainous regions in arctic northern Russia.

Quartz is the name of a large group of minerals comprised of silicon dioxide. Quartz is the most abundant mineral on the Earth’s surface, and it can be found on all seven continents. It is best known as its gemstone varieties Amethyst, Citrine, and Rock Crystal Quartz. Quartz crystals are distinctive six-sided prisms with six-sided pyramid terminations. Quartz specimens are attractive and sought after as decorative items.

Jade has been treasured for some 7,000 years for its unique luster, lovely color and impeccable toughness. This precious gem has always had special significance in many Asian cultures and can be compared to the West's admiration of diamonds and gold. For centuries, nephrite jade and jadeite were considered one and the same. It was not until 1863 that they were identified as different minerals with a similar appearance and properties. Nephrite is a tough rock comprised of intergrown crystals of minerals from the tremolite-actinolite solid solution series, part of the amphibole group.

Vesuvianite, also known as Idocrase after its discovery at Mount Vesuvius, has crystals that are prismatic and glassy. It is usually green or chartreuse in color, but may be found in yellow to brown, yellow-green, red, black, blue or purple hues.

Capiz Shells come from the province of Capiz and the island of Samal in the Philippines. The shells are often called windowpane oysters because they have been harvested for thousands of years for use as windowpanes. Capiz shells are also used today in chandeliers, lampshades, decorative objects, clothing decoration and jewelry. The shells are translucent in their natural state and turn opaque when heated. When shells are heated for longer periods of time, they turn a smoky brown color. Shells are also dyed fashionable colors.

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."

Gadolinium gallium garnet, thankfully abbreviated to GGG, is a man-made diamond simulant that entered the market in the 1960's. Today it is rarely used as a gemstone, and is instead manufactured for optical and industrial uses. The Czochralski method of gem synthesis involves the melting of various elements in a platinum crucible. A small gem crystal (called a seed) and attached to a rod is then dipped into the melt and slowly pulled away as the crystal grows around the seed. For this reason, the Czochralski method is also known as crystal pulling. Synthetic gems have the same chemical, optical, and physical properties of their natural counterparts, but are a more cost-effective alternative to a natural gem.

Phosphosiderite is a vibrant purple orchid color and is a relative newcomer to the world of gemstones as it was only discovered in the late 19th century. Fine quality phosphosiderite is hard to come by and this opaque gemstone may contain veins of yellow. In addition to purple, phosphosiderite occurs in colors ranging from white, pink, red, violet red and colorless.

The term triphane originated as another name for spodumene, but more recently has been used in reference to colorless to light yellow transparent spodumene. Triphane's name is derived from a Greek term meaning 'three aspects', due to its distinctive trichroism.