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Shells are the protective outer coverings from various animals. Most of the shell used in jewelry comes from helmet conchs, mollusks, black-lipped oysters, and abalone. The earliest known shell jewelry dates to 82,000 years ago from a site in Morocco. It is thought that shell’s first use as an ornamental material was a byproduct of the search for food. Shell is best known for its use in mother-of-pearl buttons and knife handles. Cameo carvers take advantage of the different colored layers of shell to create images of beautiful women and classical scenes.

Sinhalite is named after its discovery location, Sri Lanka, using its Sanskrit name, Sinhala. This rare gemstone was, until recently, only found in Sri Lanka, but is now mined in Tanzania, Madagascar and Burma. Often occurring in green to brown to brownish black hues, it was once mistakenly believed to be a variety of olivine.

Glass has been used for thousands of years as a decoration. It is sometimes employed as a gemstone simulant, but is often appreciated entirely upon its own merits, especially when formed with a high level of artistry.

Cubic Zirconia (abbreviated CZ) is the best-known man-made diamond simulant. A simulant is any material, natural or created by man, which imitates the appearance of a natural gem whereas a synthetic gem is man-made but must have a natural counterpart that duplicates the chemical, optical, and physical properties of the natural gem. While it's often touted as the most popular diamond simulant, cubic zirconia is also a synthetic gem. Natural crystals of cubic zirconia have only been found as inclusions in zircon.

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.

Maw-sit-sit is a rock composed primarily of kosmochlor with varying combinations and amounts of other minerals. Due to its close resemblance to jade, it was believed to be a variety of jade up until the 1960s. This gem is opaque saturated green with dark green to black veining or mottling.

Displaying gorgeous deep raspberry pinks, pezzottaite is a relatively new gemstone that has been subject to much confusion due to its similarities with red beryl. Pezzottaite has a variety of misnomer trade names including Madagascan raspberyl, raspberyl and raspberry beryl. Pezzottaite was first thought to be a new variety of beryl. Pezzottaite upon analysis was found to be a new mineral variety, with a trigonal crystal structure and that it contained cesium and lithium, which differed from beryl, making its trade names misleading.

Kyanite is named for the Greek word for blue, kyanos. And what a blue! Fine Nepali kyanite can resemble the finest sapphire. Kyanite was a gem far better known to mineral collectors until more recent finds in the Kali Gandaki river region of west central Nepal, the first source to produce a significant amount of facet grade kyanite. Prior to the Nepal discoveries, Brazil was a major source of mineral specimen material, but kyanite also occurs in a variety of locations around the world. More recent kyanite discoveries have yielded additional colors, including orange and green.

Adularescent labradorite with a multi-colored glow is sometimes called rainbow moonstone. Rainbow moonstone is colorless and highly transparent and it displays an amazing optical phenomenon called adularescence. Labradorite is a plagioclase feldspar and a member of the triclinic crystal system. Internally repeating feldspar layers scatter the light that enters the stone creating a mystical glow reminiscent of moonbeams. This glow comes to life, rolling across the gems surface, when it is moved.

Also known as Mount St. Helens stone, helenite is a man-made stone that originates from the ashes of the Washington State Mount St. Helens eruption in 1980. While the volcanic ash was being removed, it was discovered that it contained glass particles that turned a beautiful green color when heated. This glass is commonly made and fashioned into jewels that may be green, red or blue.

Sugilite belongs to a class of minerals known as silicates and is a member of the milarite group. A relatively recent addition to the realm of gemstones, sugilite was discovered in 1944 by a Japanese geologist, Ken-ichi Sugi. The mineral is named in his honor. The original find was a yellowish brown variety that was of no interest to the jewelry industry. It was not until 1979 that the first massive aggregates, exhibiting a rich purple color, were discovered in a South African manganese mine. This material was attractive and gained the attention of the gemstone industry. It is predominantly found in the form of cabochons of various shapes and sizes, but has also been used as a component in intarsia jewelry. It is sometimes carved into decorative objects and fashioned into beads.

The name Psilomelane was discredited as a distinct mineral variety but the name is still used as group name for hard black manganese oxides of which Romanechite and Hollandite are components. Psilomelane means smooth and black in Greek which aptly describes its appearance. It is often found in botryoidal masses with submetallic luster.